ADELAIDE is hopeful star ruckman Sam Jacobs’ ankle injury is so minor that the big man can still take his place against the Brisbane Lions next weekend.

Jacobs badly rolled his ankle in the second term against Essendon on Sunday and was helped off Adelaide Oval in obvious pain.

His left ankle gave way when he landed during a marking contest and he immediately reached down to hold it.

Crucial to Adelaide’s structural set-up, Jacobs left the field on crutches at half-time, but coach Don Pyke said initial signs suggested the sprain was on the minor end of the scale.

"He rolled his ankle, the report at the moment is that it’s a low-grade strain, so we’re pretty hopeful with treatment he could be available next week," Pyke said.

"Once he came off the decision from the doctor was probably a no-risk policy which is wise in the circumstances … hopefully he can rehab that and give him every chance for next week."

Should Jacobs not recover in time to take on the Lions, Pyke pointed to emerging ruckman Reilly O’Brien as his probable replacement.

O’Brien has consistently excelled at SANFL level for the past 18 months and on Sunday amassed 34 hit-outs, 15 possessions a goal against Port Adelaide.

When Jacobs went down on Sunday it left to Josh Jenkins to carry the bulk of the ruck burden, but Pyke said that he would be unlikely to do so again if Jacobs was ruled out.

"If Sam doesn’t end up playing we’ve elevated Reilly O’Brien, who’s been playing well in the SANFL and is another one who’s there … there’s a fair chance that he would possibly get an opportunity," Pyke said.

Captain Taylor Walker could also line up against the Lions.

Walker missed Sunday’s 82-point win over the Bombers because of an ankle injury.

Pyke said the forward completed a “light session” on Sunday.

“I think he’ll be up running as early as tomorrow,” Pyke said.

“He has no soreness at the moment, which is great.

“We’d hope he’d train for us Wednesday and be ready to go next week.”

The Crows took the foot off the pedal late in their massive win, with the Bombers kicking four of the final five goals.

Essendon’s late surge cost Adelaide fourth spot at the end of the round; the Crows now sit fifth behind Geelong by 0.1 per cent.

Pyke said the end of the game was disappointing, not simply because of percentage, but because the side drifted from the plan.

"It’s probably not so much about the percentage and bits and pieces, it’s more our ability to stay to the way we want to play," he said.

"For the majority of the night we played some good footy, we’ve still got some areas we’ll keep working on but the last five minutes … there were a few breakdowns."