'Machanidas, filled with confidence and regarding the attack of the Achaeans almost as a godsend, as soon as he heard that they were concentrated at Mantinea, addressed the Lacedaemonians at Tegea in terms suitable to the occasion, and at once on the next day shortly after daybreak began to advance on Mantinea. He himself led the right wing of the phalanx, and placed the mercenaries in parallel columns on each side of the van with wagons behind them charged with a quantity of engines and missiles for catapults. At the same time Philopoemen, dividing his army into three parts, led it out of Mantinea, taking by the road that starts from the temple of Poseidon the Illyrians and heavy-armed cavalry, together with all his mercenaries and light-armed troops, by the next road to the west the phalanx, and by the next the Achaean cavalry. He first of all occupied with his light-armed troops the hill in front of the city which rises at a considerable height above the road called Xenis and the above temple, and next to them on the south he placed the heavy-armed cavalry, with the Illyrians adjacent to them. Next to these on the same straight line he stationed the phalanx in several divisions at a certain distance from each other along the ditch that runs from the temple of Poseidon through the plain of Mantinea and terminates at a range of hills forming the boundary of the territory of Elisphasia. Then next the phalanx on his right wing he posted the Achaean cavalry under the command of Aristaenetus of Dyme. On the left wing under his own command was the mercenary cavalry in close order.
As soon as the enemy were well in view he rode along the divisions of the phalanx and addressed them in a few brief words, pointing out the importance of the coming battle. Most of what he said was not distinctly heard, because, owing to the soldiers' affection for him and reliance on him, such was their ardour and zeal that they responded to his address by what was almost a transport of enthusiasm, exhorting him to lead them on be of good heart. The general tenor, however, of what he attempted to point out to them whenever he got the chance, was that in the present battle the enemy were fighting for shameful and ignominious slavery and they themselves for imperishable and glorious liberty.
Machanidas at first looked as if he were about to charge the enemy's right with his phalanx in column, but on approaching, when he found himself at the pro distance he wheeled to the right, and deploying into line made his own right wing equal in extent to the Achaean left, placing his catapults at certain intervals in front of his whole army. Philopoemen, seeing that Machanidas' plan was by shooting at the divisions of the phalanx to wound the men and throw the whole force into disorder, gave him not a moment's leisure, but vigorously opened the attack with his Tarentines in the neighbourhood of the temple of Poseidon where the ground was flat and suitable for cavalry. Machanidas, when he saw this, was obliged to likewise and order his own Tarentines to charge at the same time.
At first the Tarentines alone were engaged, fighting gallantly, but as the light-armed infantry gradually came up to the support of those who were hard pressed, in quite a short time the mercenaries on both sides were mixed up. They were fighting all over the field, in a confused crowd and man to man. For long the struggle was so equally balanced that the rest of the army, who were waiting to see to which side the cloud of dust was carried, could not make this out, since both long remained occupying their original positions. But after some time the tyrant's mercenaries prevailed by their superior numbers and skill, for they were well trained. This is generally what is liable to happen, since by as much as the civic force of a democracy is more courageous in action than the subjects of a tyrant, by so much will a despot's mercenaries in all probability excel those who serve for hire in a democracy. For as in the former case one side is fighting for freedom and the other for slavery, so in case of the mercenaries the one force is fighting for manifest improvement in their situation and the other for evident damage to their own; since a democracy when it has destroyed those who conspire against it no longer requires mercenaries to protect its freedom, but a tyranny, the more ambitious its aims, requires all the more mercenaries. For since it injures more people it has the more conspiring against it, and in general it may be said that the safety of despots depends on the affection and strength of their foreign soldiers.
So it was at present also. The mercenaries of Machanidas fought with such desperate courage and force that the Illyrians and cuirassed troops who supported the mercenaries could not resist the attack, but all gave way and fled in disorder towards Mantinea, which was seven stades distant. This occasion afforded evidence sufficient to convince all of what some have doubted, the fact that most results in war are due to the skill or the reverse of the commanders. It is perhaps a great feat to follow up initial success, but it is a much greater one upon meeting with reverse at the outset to keep cool-headed, to be able to detect any lack of judgement on the part of the victors and take advantage of their errors. Indeed we often see those who already seem to have gained the day totally worsted shortly afterwards, and those who at first seemed to have lost it unexpectedly turn the tables and restore the situation by their dexterity. This was very clearly illustrated by the conduct of both the two commanders on the present occasion. For when the whole Achaean mercenary force gave way and their left wing was broken, Machanidas, instead of remaining on the field to outflank the enemy on one side and by a direct attack on the other to strike a decisive blow, did neither, but with childish lack of self-control rushed forward to join his own mercenaries and fall upon the fugitives, as if terror alone were not sufficient to drive them as far as the gate once they had given way.
The Achaean commander did his best to rally the mercenaries, calling on their leaders by name and encouraging them, but when he saw that they were forced back he neither fled in dismay, nor lost heart and gave up hope, but posting himself on the wing of his phalanx, and waiting till the pursuers had passed by and left the ground on which the action had taken place clear, he at once wheeled the first section of the phalanx to the left and advanced at the double but without breaking his ranks, and rapidly occupying the ground which the enemy had abandoned, both cut off the pursuers and at the same time outflanked the Spartan wing. He exhorted the men of his phalanx to be of good heart and wait until he gave the order for a general charge. He commanded Polyaenus of Megalopolis to collect rapidly all those of the Illyrians, cuirassed infantry, and mercenaries who were left behind or had evaded the pursue, and to support the wing of the phalanx and wait for the return of the pursuers. The Lacedaemonian phalanx now, without orders but elated by the success of the light-armed troops, levelled their spears and charged the enemy. When increasing they reached the edge of the ditch, partly because they had no longer time to change their minds and retrace their steps as they were at close quarters with the enemy, and partly since they made light of the ditch as its descent was gentle and it had neither water nor bushes at the bottom, they dashed through it without hesitating.
When he saw that the chance of smiting the enemy that had so long been present to his mind had at length arrived, Philopoemen ordered the whole phalanx to level their spears and charge. When the Achaeans, like one man and with a loud cheer that cast terror into their foes, rushed on them, those of the Lacedaemonians who had broken their ranks and descended into the ditch, lost courage as they mounted the bank to meet the enemy above their heads and took to flight. The greater number of them perished in the ditch itself, killed either by the Achaeans or by each other. And this result was not due to chance or to momentary luck, but to the sagacity of the commander in at once protecting his men by the ditch. This he did not with the desire to avoid an encounter as was supposed by some, but calculating everything accurately like the expert general he was and foreseeing that if Machanidas, when he came up, led his force forward without reckoning on the ditch, the phalanx would suffer what I have just described as actually happening to it, whereas if the tyrant took into consideration the difficulty presented by the ditch, and changing his mind, seemed to shirk an encounter, breaking up his formation and exposing himself in long marching order, he would then without a general engagement himself secure victory while Machanidas would suffer defeat. This has already happened to many, who after drawing up in order of battle, being under the impression that they were not equal to engaging the enemy, either owing to their position or owing to their inferiority in numbers or for any other reason, have exposed themselves in a long marching column, hoping as they retired to succeed, by the sole aid of their rearguard, either in great the better of the enemy or in making further their escape. This is a most frequent cause of error on the part of commanders.
But Philopoemen was by no means deceived in his anticipation of what the result would be; for the Lacedaemonians were completely routed. When he saw his phalanx victorious and everything going on splendidly for himself he turned his mind to the remainder of his project, which was to prevent the escape of Machanidas. Knowing the in his unwise pursuit he had been cut off together with his mercenaries on the side of the ditch lying nearest the town, he was waiting for his reappearance. Machanidas on observing when he had desisted from the pursuit that his troops were in flight, and on realizing that he had blundered and thereby lost the day, at once attempted to make the mercenaries he had round him close up and force their way in a compact body through the scattered ranks of the pursuers. Some of them with this end in view remained with him at first, hoping thus to get off safe, but when they got up to the ditch and saw that the Achaeans were holding the bridge over it, they all lost heart and dropped off from him, each attempting to save himself as best he could. Meanwhile the tyrant, despairing of making his way across the bridge, rode along the ditch trying with all his might to find a crossing.
Recognizing Machanidas by his purple cloak and the trappings of his horse, Philopoemen left Alexidamus with orders to guard the passage carefully and spare none of the mercenaries, as they were the men who had always maintained the power of the Spartan tyrants. Taking with him Polyaenus of Cyparissa and Simias, who acted at the time as his aides-de-camp, he followed the tyrant and those with him — there were two who had joined him, Arexidamus and one of the mercenaries — along the opposite side of the ditch. When Machanidas, on reaching a place where the ditch was easily passable, set spurs to his horse and forced it across, Philopoemen turned to meet him. Giving him a mortal wound with his spear and adding yet another thrust with the lower end of it, he slew the tyrant hand to hand. Arexidamus suffered the same fate at the hands of the two officers who rode with Philopoemen, and after the death of the two the third man, despairing of crossing, sought safety in flight. When both had fallen Simias and his companion stripped the bodies and taking the armour and the head of the tyrant hastened back to the pursuers, eager to show to their men those proofs of the death of the enemy's commander, so that believing the evidence of their eyes they might with increased confidence and fearlessness continue the pursuit of the enemy as far as Tegea. And the sight did as a fact much contribute to the spirit of the soldiers; for it was chiefly owing to this that they captured Tegea by storm, and a few days after were encamped on the banks of the Eurotas, already in undisputed command of the country. For many years they had been unable to repulse the enemy from their own land, and now they themselves fearlessly pillaged Laconia, having suffered little loss in the battle, but having not only slain as many as four thousand Lacedaemonians but captured a still greater number and made themselves masters of all the baggage and arms.' (Polybius: The Histories book 11).
The Achaeans at that time were at war with Machanidas, the tyrant of Lacedaemon, who, having a strong army, watched all opportunities of becoming entire master of Peloponnesus. When intelligence came that he was fallen upon the Mantineans, Philopoemen forthwith took the field, and marched towards him. They met near Mantinea, and drew up in sight of the city. Both, besides the whole strength of their several cities, had a good number of mercenaries in pay. When they came to fall on, Machanidas, with his hired soldiers, beat the spearmen and the Tarentines whom Philopoemen had placed in the front. But when he should have charged immediately into the main battle, which stood close and firm, he hotly followed the chase; and instead of attacking the Achaeans, passed on beyond them, while they remained drawn up in their place. With so untoward a beginning the rest of the confederates gave themselves up for lost; but Philopoemen, professing to make it a matter of small consequence, and observing the enemy's oversight, who had thus left an opening in their main body, and exposed their own phalanx, made no sort of motion to oppose them, but let them pursue the chase freely, till they had placed themselves at a great distance from him. Then seeing the Lacedaemonians before him deserted by their horse, with their flanks quite bare, he charged suddenly, and surprised them without a commander, and not so much as expecting an encounter, as, when they saw Machanidas driving the beaten enemy before him, they thought the victory already gained. He overthrew them with great slaughter (they report above four thousand killed in the place), and then faced about against Machanidas, who was returning with his mercenaries from the pursuit. There happened to be a broad deep ditch between them, alongside of which both rode their horses for a while, the one trying to get over and fly, the other to hinder him. It looked less like the contest between two generals than like the last defence of some wild beast brought to bay by the keen huntsman Philopoemen, and forced to fight for his life. The tyrant's horse was mettled and strong; and feeling the bloody spurs in his sides, ventured to take the ditch. He had already so far reached the other side, as to have planted his fore-feet upon it, and was struggling to raise himself with these, when Simmias and Polyaenus, who used to fight by the side of Philopoemen, came up on horseback to his assistance. But Philopoemen, before either of them, himself met Machanidas; and perceiving that the horse with his head high reared covered his master's body, turned his own a little, and holding his javelin by the middle, drove it against the tyrant with all his force, and tumbled him dead into the ditch. Such is the precise posture in which he stands at Delphi in the brazen statue which the Achaeans set up of him, in admiration of his valour in this single combat, and conduct during the whole day.
(Plutarch: The Life of Philopoemen).
The phalanxes of both armies were in the centre Philopoemen now strategos of the Achaean League had 20,000 armed in the Macedonian manner. Machanidas forces were made up mostly of mercenaries. Machanidas had light cavalry on the left with medium infantry, light cavalry and light infantry on the right. Machanidas also placed catapults to the front.
The Achaeans had heavy cavalry on their right with medium infantry and light cavalry and infantry on the left.