When Warwick reached the Lancastrian left flank, commanded by Lord Grey of Ruthin, treachery ensued. Grey had his men lay down their weapons and simply allow the Yorkists to have easy access into the camp beyond. This treachery was the result of a secret message from Lord Grey to March saying that he would change sides if the Yorkists would back him in a property dispute with Henry Holland, 3rd Duke of Exeter (his maternal cousin). Certainly Warwick had ordered his men not to lay violent hands on ordinary soldiers – especially those wearing the black ragged staff of Lord Grey's men. There may also have been inducements and promises of high office by Warwick. Grey became Treasurer of England in 1463. After this, the battle lasted a mere thirty minutes. The defenders were unable to manoeuvre inside the fortifications, and fled the field as their line was rolled up by attacking Yorkists.