Essendon key position prospect, Scott Gumbleton, will miss the next three to four weeks after straining a medial ligament in his left knee during a training drill this morning.

Team Manager, David Calthorpe, said the 19-year-old was injured during a regulation drill that involved tackling.

""This is one of those unfortunate incidents that can occur where he was tackled and, unfortunately, strained his left knee,"" Calthorpe said.

""We are optimistic he will only miss three to four weeks and then make a return to footy.

“He will have scans on Monday to confirm our early diagnosis and make sure there is no other damage.

""The sad thing for Scott is that he had been training strongly following a hamstring injury in the NAB Cup and would have resumed this weekend if the Bendigo Bombers didn’t have a bye.”