Essendon’s star forward Joe Daniher faces at least a month on the sidelines with a leg injury.

The Bombers have confirmed Daniher damaged his calf in training.

He is expected to miss at least four weeks.

It comes just one day after Bombers coach John Worsfold said Daniher was on track to to return to the Essendon line-up in its round 1 clash with GWS.

He only played seven games last year, falling victim to osteitis pubis.

“Joe was progressing strongly in his recovery from an unrelated injury, so this soft-tissue setback is clearly disappointing for both him and the club,” Essendon GM of Football Dan Richardson said in a club statement.

“Joe remains positive and is committed towards his rehabilitation program as he works towards a return to the senior side early in the upcoming home-and-away season.”

It’s another blow for the Bombers’s forward line, which will be without swingman Cale Hooker during the opening part of the season due to injury.