The problem for Bruce was to keep the English out of Stirling till St John's day had passed. In good time he had selected and laid out the inevitable field of battle with military prescience of the first order. He had mustered his forces in the Torwood, in a position commanding the approach to Stirling from the south; and on the morning of Saturday, the 22nd of June, on news of the approach of the English, he marched them to the chosen spot on a plain some two miles south of Stirling within the last large loop of the Bannock Burn, called the New Park—a hunting-ground of the Scots kings. The Park was a piece of firm ground rising on the north and west into the swelling ridges of Coxet Hill near St Ninian's, and Gillies Hill on the left of the Bannock above the bend towards the Forth. Eastwards it fell away into a marshy tract filling the angle of the two rivers and intersected by watercourses. Southwards, too, the hard ground was broken by two morasses—Halbert's Bog and Milton Bog—between the Park and the Bannock. Bruce rested his right wing on the steep bank of the Bannock below Gillies Hill; his left wing stretched away past St Ninian's nearly to the gates of Stirling; his rear was protected by Gillies Hill and the Bannock behind. The English would be compelled to advance either across the Bannock between Parkmill and Beaton's Mill—a breadth of a short mile, free from precipitous banks—to the line of hard ground, with a contracted front, to be immediately divided by the intervening bogs; or else along the line of low and marshy flat between the Park and the Forth. To reduce the superiority of the English cavalry, Bruce had industriously dug pits along the parts of the firm route by which they would probably, if not inevitably advance—pits a foot wide, round, and deep as a man's knee, honeycombing the ground; and these holes he covered loosely with a disguise of brushwood, turf, and grass. He is also said to have inserted in them stakes shod with iron points. Sir Thomas de la Moore mentions long transverse trenches, similarly covered so as to bear men aware of them, but not horses. Later writers add that Bruce strewed the ground with calthrops, or metal spikes, to cripple the English horses. He himself had determined to fight on foot.

Bruce marshalled his troops in four divisions, facing south-eastwards. The van was led by Randolph. The second and third divisions were ranged behind the wings of the van; the former, to the right and resting on the Bannock, led by Sir Edward Bruce, the latter by Walter the Steward ('that then was but a beardless hyne') and Douglas. The rearguard, consisting of the men of Carrick, Argyll, Cantyre and the Isles, was stationed right behind the van at some interval, under the immediate command of Bruce himself. All the divisions could thus be promptly massed on the English whether they should select the higher or the lower line of advance. It was of the very first importance that no detachment of the English should be allowed to outmanœuvre the main body of the Scots and throw themselves into Stirling; and Randolph, who held the most advanced position, was especially charged to guard against this fatal contingency. The non-combatants retired behind the hill in the rear, afterwards named from them the Gillies' (that is, Servants') Hill.

The dispositions of the English army are not known in certain detail. There is little help in Barbour's statement that it was divided into ten companies of 10,000 each. We know that the van was led by the Earl of Gloucester; and that, if Robert of Reading and the Monk of Malmesbury may be relied on, the appointment of Gloucester was hotly resented by the hereditary constable, the Earl of Hereford. The King's bridle was attended by Sir Aymer de Valence and Sir Giles d'Argentine, the latter of whom was regarded as the third knight in Christendom, and had been released from captivity at Salonica in the end of the preceding year through Edward's urgent representations to the Emperor, and even to the Empress, of Constantinople.

At sunrise on Sunday, June 23—the eve of St John—the Scots heard mass. Bruce then devoted special attention to the pits that were still preparing. After midday—the Scots observed the fast on bread and water—the English were reported to be advancing from the fringe of the Torwood. Bruce issued his final orders. Then he is said to have addressed his men in terms of high resolution, bidding every man depart that was not ready for either alternative—to conquer or to die. Not a man moved from the ranks. More than five centuries later, at Balaclava, 'Men,' cried Sir Colin Campbell, 'you must die where you stand.' 'Ay, ay, Sir Colin, we'll do that,' was the cheery response. Such, too, was the spirit of the same race on the field of Bannockburn.

At this point, according to Barbour, Douglas and Sir Robert de Keith (hereditary marshal) proceeded, by order of Bruce, to reconnoitre the enemy's advance. They returned with such a report of the numbers and equipment of the English as they deemed it prudent to render to Bruce only 'in great privity.' Bruce, however, put a bold face on the situation, and directed them, says Barbour, to spread a depreciatory account of the enemy.

The main body of the English appears to have halted while the leaders should take counsel. But Gloucester, with the vanguard, ignorant of this and ardent for the fray, dashed through the Bannock and advanced on the Park, where Sir Edward Bruce was ready to receive him. King Robert himself was riding in front of Sir Edward's division on a small palfrey, with only a battle-axe in hand. On his basnet, according to Barbour's haberdashery, he wore a hat of jacked leather, surmounted by 'a high crown, in token that he was a king.' Some of the English knights, says the Monk of Malmesbury, rode out between the lines and flung their challenges to the Scots. Sir Henry de Bohun, a knight of the house of Hereford, spurred at Bruce himself, and Bruce, swerving at the critical moment of attack, rose in his stirrups as de Bohun passed and clove his head at a stroke, the shaft of his axe shivering in his hand. It may be remarked incidentally that Gray calls the luckless knight Sir Piers de Mountforth. The Scots pressed forward; the English fell back; but Bruce prudently soon recalled his men from the conflict. The Monk of Malmesbury, however, acknowledges that there was 'sufficiently keen fighting, in which Gloucester was unhorsed.' It is not surprising that the leading Scots remonstrated earnestly with Bruce for exposing himself to such an unequal chance. According to Barbour, he made no answer, only regretting the breaking of his good axe-shaft. There can hardly be any doubt that Bruce took the risk deliberately, in calculated reliance on his dexterity and strength, and not without a judicious eye to the moral effect on both armies. The feat, in any case, damped the ardour of the English and raised the spirit of the Scots.

Almost contemporaneously with the advance of Gloucester, Clifford and Beaumont, with 300 men-at-arms—Gray, whose father rode with them, says 300, while Barbour makes them 800—hurried along the lower ground on the English right towards Stirling. Their evident object, as Barbour says, was to relieve the castle; but the Lanercost chronicler ingenuously explains that it was to prevent the Scots from escaping by flight. Randolph, strangely ill-served by his scouts and by his eyes, if Barbour be right, is said not to have been aware of the movement till he received a sharp message from Bruce (as if Bruce's attention was not fully engaged elsewhere), telling him significantly that a rose had fallen from his chaplet. This is sheer monkish imagination. Gray makes no mention of this incredible inadvertence, but represents Randolph as fired by the news of Bruce's repulse of the English van; and the Lanercost chronicler states that the Scots deliberately allowed the advance of the party. Of course they did; Randolph undoubtedly descried them the moment they debouched on the carse. To do so was no less important than it was for Sir Edward to be ready for Gloucester's onset. The next step for Randolph was to tackle his enemy at the right spot and not elsewhere. With a strong detachment he rapidly traversed the wooded edge of the Park, so as to converge upon the English horsemen at the narrow neck between St Ninian's and the Forth—the only point, in fact, where he could calculate upon holding them without moving his whole division down into the low-lying ground (if even that would have done it), and deranging the order of battle. When they were 'neath the kirk,' he issued from the wood and menaced their further progress.

'Let us retire a little,' said Beaumont; 'let them come; give them the fields.'

'Sir,' remarked Sir Thomas Gray, the elder, 'I suspect if you give them so much now, they will have all only too soon.'

'Why,' rejoined Beaumont tartly, 'if you are afraid you can flee.'