Injured Adelaide ruckman Sam Jacobs will not return to AFL action on Sunday.

Jacobs rolled his ankle in the second quarter of Adelaide’s win over Essendon in Round 19 and was replaced in the ruck by first-gamer Reilly O’Brien for last Saturday night’s game against Brisbane.

Jacobs started running again on Thursday, but Crows senior coach Don Pyke said the 28-year-old wouldn’t be fit in time for the trip west.

“That ankle (injury) was a little bit worse than we initially thought,” Pyke said.

“He (Jacobs) will miss again, which means Reilly O’Brien gets another look and that’s great for him.”

O’Brien will take on Dockers giant Aaron Sandilands at Domain Stadium.

Pyke said it would be a good challenge for the promising 21-year-old.

“I thought his (O’Brien’s) game last week showed that he was comfortable at the level,” he said.

“He certainly wasn’t overawed by his first game. Knowing 'ROB', I’ll back him in (against Sandilands).”

Wingman Paul Seedsman, who suffered a corked buttock in the first quarter against the Lions, remains in doubt.

“Seeds is a bit sore, so we’ll assess how that looks and weigh it up at match committee,” Pyke said.

“It (the cork) has probably caused him a little bit more soreness than we thought and then you’ve obviously got some bleeding around the hamstring area, so it’s one of those ones we’ll weigh up whether it’s worth taking the risk or not.”

Pyke confirmed experienced midfielder Scott Thompson would return after being managed last weekend. Young forward Mitch McGovern (managed) and running half-back Ricky Henderson (Achilles) are also available for selection.

Jacobs is likely to be fit for next week's Showdown.