Once across the border, Maxwell was informed by Lord Sinclair that he was now taking command of the Scottish army, supposedly at the behest of the King. With the enemy already harrying their flanks and the main English force visible, this was a disastrous moment for Sinclair’s announcement. Factions now appeared in the Scottish ranks as those loyal to Maxwell disputed with those who rallied to Sinclair; the latter group probably motivated more by the fact that Sinclair was a favourite of the King rather than trust in his abilities.

As the raiding army moved through the debatable lands, pillaging and burning as they went, the English patrols had been kept at bay by the Scottish artillery. But Wharton's men maintained their harrying and shadowing of the Scottish advance. As the Scots turned south towards them to deploy and advance in battle array, Wharton drew up the main English force on Hopesike Hill, blocking the route south into England. He also detached 500 cavalry under Sir William Musgrave to ‘prick’ (so called because the mounted troops would use their lances to prick the enemy without becoming embroiled in hand-to-hand combat) at the Scottish left flank. Musgrave’s attacks where remarkably efficient, his fast moving troops harrying the Scots before wheeling about, reforming and attacking again.

The troops on the Scottish left flank were quickly disordered by the English lancers and in their desperate attempts to withdraw crashed into the troops to their right. Those on the far right were crushed between their own troops and the boggy ground to their right, some being pushed into the bog. Confusion reigned amongst the leaderless Scots, many of those in the rear breaking and fleeing. Other troops quickly followed and many of those that did not flee surrendered in their droves. Wharton, from his vantage point on Hopesike Hill could see the chaos developing below him and so he now advanced his troops to Arthuret Howe. Thinking perhaps that it was the vanguard of the main English army that was advancing towards them, disorder amongst the Scots now became a rout, as artillery and baggage was abandoned in their flight. Musgrave’s horse pursued the fleeing Scots many of whom drowned in their attempts to cross the Esk, and driving many others on to seek a safe escape on foot through the marshy ground of the great Solway Moss.

Few Scottish troops were killed on the battlefield. Far more were drowned trying to cross the River Esk, where several hundred may have perished, but many more were captured, including Maxwell and Sinclair and several other senior nobles.