When reinforcements led by Dundee arrived at Blair on 25 July, Murray withdrew, while Mackay left Perth with around 3,500 men and moved north to support him. At Killiecrankie on 27 July, the Jacobites won a resounding victory, inflicting nearly 2,000 casualties on Mackay's army. However, nearly a third of the Jacobites were killed, including Dundee. Alexander Cannon took over as Jacobite leader, but his options were limited. Without siege equipment, he could not capture a port, making resupply almost impossible, while lack of cavalry made Jacobite soldiers vulnerable in the open. Time was on Mackay's side, so long as he avoided another ambush.