Essendon are relying on Tom Bellchambers' final stages of injury rehabilitation going to plan to avoid an early-AFL season ruckman shortage with Matthew Leuenberger's unavailability.
Leuenberger is expected to miss the opening two rounds of the season, grounded by a hamstring injury suffered in the Bombers' pre-season clash with Geelong on Sunday.
Bellchambers, returning from a year-long doping ban, has gradually increased his workload since undergoing knee surgery in January.
The club expects him to line up for his first competitive hit-out since 2015 in a VFL practice match on Friday.
Ex-Brisbane big man Leuenberger, who took Essendon's No.1 ruckman mantle in place of Bellchambers last year, hobbled off after a first-quarter ruck contest against the Cats.
He will miss the Bombers' season-opener against Hawthorn on March 25 and their round-two clash with the Lions.
"He was bent right over the football, got some pressure from behind and felt a pulling sensation as he stretched over the ball," Essendon high performance manager Justin Crow said.
"He actually ended up playing a few minutes after that but eventually came off with his hamstring sore.
"We've had it scanned and it's a medial strain which is the inside of the hamstring.
"He'll be back in full training in three weeks and then probably looking to play that week."
Shaun McKernan stepped up in Leuenberger's absence, providing a good contest at the stoppages, kicking three goals, including a supergoal, and racking up 21 touches and 19 hit-outs.
McKernan will need to be elevated off the rookie list to face the Hawks.