Crows co-captain Taylor Walker has praised the efforts of ruckman Reilly O’Brien, labelling the big man’s impact as “outstanding”.

O’Brien was brought into the side in Round Three to replace Sam Jacobs, who injured his knee against Sydney.

Jacobs has been ruled out for at least three more weeks, leaving O’Brien to carry the ruck work.

“He’s grabbed the opportunity with both hands,” Walker said.

“He doesn’t leave a stone unturned, works hard and is a great guy.

“(Elliott) Himmelberg has come in and really complemented him well.”

O’Brien recorded 44 hit-outs against Fremantle in Round Seven, along with 22 disposals and five marks.

MATCH REPORT: Crows down Dockers at Adelaide Oval

Ahead of this weekend’s clash with Port Adelaide, Walker said he embraced playing away Showdowns in front of a hostile crowd.

“It makes it even better that we’re six and seven (on the ladder),” Walker said.

“Showdowns give our players a little taste of what finals footy is like.

“It should be another great Showdown this weekend.”

Port Adelaide co-captain Ollie Wines said the defence would keep a special eye on danger man Eddie Betts, who has kicked eight goals in the past five Showdowns.

“I’ve never played a Showdown where Eddie doesn’t show up,” Wines said.

“It’s pretty tough, I think they try to be physical with him, but he has that license to run and crumb.

“You just hope to catch him on an off day.”