LIKELY No. 1 draft pick Tom Boyd is set to miss between four to six weeks with an ankle injury despite initial scans revealing no fracture.

Boyd's injury marred Vic Metro's 19-point over Western Australia in the NAB AFL Under-18 Championships at Patersons Stadium on Saturday.

The key forward kicked three goals in a dynamic first quarter, but landed awkwardly on his left ankle after taking another mark inside 50.

Boyd ended the game on crutches and with his foot in a moon boot. 

More scans are expected through the week to determine the severity of the injury.

The injury means Boyd will be unavailable for Metro's final two games of the championships, against South Australia at Simonds Stadium on June 28 and Vic Country at Etihad Stadium on July 3. 

Standing at 199cm, Boyd has been touted as the No. 1 pick in this year's draft for his contested marking ability and his mobility around the ground.

He kicked six goals for Metro against NSW/ACT the week before and looked menacing against WA, before being grounded by the ankle injury.