Essendon star duo Michael Hurley and Jake Stringer are doubtful to reach full fitness for the Bombers' Round 1 clash next month, while captain Dyson Heppell has been tipped as a certain starter.

Hurley was hospitalised after sustaining a leg/hip infection, remaining under care and away from training duties while Stringer has suffered an Achilles injury, further delaying his 2021 preparations.

Stringer is set to abide by a strengthening regimen instead of returning to full training after aggravating the injury during match simulation, adding to the growing list of casualties at Tullamarine.

Speaking on SENBombers great Tim Watson said the circumstances of Hurley's injury have been frustrating for all involved.

“It was a hip infection, he was in hospital for five days and they were trying to contain the infection at that time,” Watson said.

"He’s gone home and now he’s in bed at home on strong antibiotics and they’re still trying to deal with the infection.

MELBOURNE, AUSTRALIA - FEBRUARY 10: Zach Merrett of the Bombers runs with the ball from Michael Hurley of the Bombers during the Essendon Bombers AFL Intra-Club Match at The Hangar on February 10, 2018 in Melbourne, Australia. (Photo by Michael Dodge/Getty Images)

"The fact that it’s two weeks now that he’s almost been inactive, your muscles really start to wither quickly when you’re on your back like that so that’s got to be real concern.”

While the incumbent pairing will face a tight deadline to play against Hawthorn at Marvel Stadium on March 20 to kick-ff their premiership campaign, Heppell has been locked in for selection after overcoming foot and ankle complaints.

Speaking to The Herald Sun, Essendon football boss Josh Mahoney revealed the Bombers' captain has returned to full training in a new role under coach Ben Rutten.

“Dyson has been managed really well by the medical and high performance team he’s now essentially in full training. He is expecting to play the pre-season games and he’s playing a new role off half back. He gives the defensive some real experience which is important,” he said.

Essendon Bombers Training Session
GOLD COAST, AUSTRALIA - AUGUST 25: Dyson Heppell during an Essendon Bombers AFL training session at Metricon Stadium on August 25, 2020 in Gold Coast, Australia. (Photo by Matt Roberts/Getty Images)

“It was a good decision to get a procedure done at the end of the season and he’s looking forward to getting out there as captain. It’s a decision based on him adding some experience to the defence but also the physical requirements of that role versus the midfield.”

Following on from their Round 1 clash against Hawthorn, Essendon will face Port Adelaide, St Kilda and Sydney in their opening month of the season.