ESSENDON is hopeful captain Dyson Heppell will miss just one match after having surgery on an injured thumb.

Heppell underwent on operation on Wednesday morning and won't play against Adelaide at Marvel Stadium on Friday night.

It is a blow for the Bombers as they look to snap a two-match losing streak and keep their finals hopes alive.

"We were pretty fortunate to be able to get it looked at and get him in (for surgery) straight away," coach Ben Rutten said.

"He'll miss a week ... hopefully, but we'll see how he pulls up."

While Heppell could return against North Melbourne in round 18, there is still no firm time frame on Dylan Shiel's comeback from a knee injury.

The gun midfielder has not played since round two and Rutten said his rehabilitation after surgery has gone "a little bit" slower than expected.

"That's why sometimes we're reluctant to put timelines on it because every injury and every recovery is different," Rutten said.

"It's just about how we continue to build his loads and he's an important player that we don't want to take any risks with."

MEDICAL ROOM The full AFL injury list

Rutten said Shiel is still "a couple of weeks away" from full training, while defender Aaron Francis is edging closer to a return to action.

Francis has not played since round 12 after being given time away to focus on his mental health.

"He's back, he's looking good and he's happy," Rutten said.

"He won't play this week anywhere, but it's just about him building himself up now.

"We want 'Frank' back for the rest of the year and performing at his best."

Essendon has suffered hits to their finals bid with defeats to flag contenders Melbourne and Geelong over the past fortnight.

But Richmond's slide has left the door ajar and the Bombers (6-9) will start favourites against Adelaide.

"We just want to keep striving to play our best footy for longer," Rutten said.

"We saw snippets of it again on the weekend (but) it's just how do we do that longer.

"If we do that more often and for longer against more opponents then the scoreboard ticks over and those wins and the ladder position takes care of itself."

Essendon has been buoyed this week by star midfielder Darcy Parish's decision to sign a new two-year deal with the club.