The Crows had long earmarked the Perth trip as a rest game for the 31-year-old spearhead, but Walker pleaded to play.

"Tex (Walker) and I had to have quite a good chat," Nicks told reporters on Thursday.

"He wants to play every week. He feels good.

"As it sits at the moment, he is performing well for us.

"But there was always a conversation around at what point are we going to make sure you can perform at your best when we get into that later part of the season.

"So this one (rest) was in the diary and we're going to stick to it.

"He wants to play ... by no means is it about performance at the moment that we're managing him, this is pre-planned."

Walker started the season in stunning goal-scoring form but has managed just two majors in his past two games, including a goalless return in last Saturday night's Showdown loss to Port Adelaide.

The former captain has booted 27 goals from eight games, second only in the competition to Carlton's Harry McKay.

Walker's absence comes amid fresh concern over on-baller Matt Crouch, who has yet to play an AFL premiership game this season because of a groin injury.

Crouch, an All Australian in 2017 when he won Adelaide's club champion award, was eyeing a return in state league ranks this weekend.

But the prolific ball-winner reported soreness after Tuesday's training and will be sent to a groin specialist.

Nicks hoped surgery wasn't required.

"It's quite concerning," Nicks said.

"We were expecting Matty maybe getting half a game at SANFL level in the next one or two weeks and his progression was going really well until Tuesday.

"Go down, speak to the specialist, get his opinion about where we now progress to.

"He was going so well and was feeling really good about getting back out with the players on the track on Tuesday, but to see him today ... it will be one to keep an eye on from here."

Australian Associated Press