ADELAIDE defender Jake Lever has been ruled out of Friday night's top-of-the-table clash with Geelong at Adelaide Oval.

Former cricketer Alex Keath will make his debut, while Rory Sloane (concussion) and Josh Jenkins (illness) are on track to play after training on Thursday morning.

Winger Wayne Milera will be given another week to recover from a calf injury.

Lever finished last Saturday night's win over Melbourne  in Darwin on the bench with a tight hamstring.

"Jake Lever won't play with hamstring tightness, so we'll try and get him organised for next week if we can," Crows coach Don Pyke said.

"It's just too tight on a six-day turnaround.

"It's nothing major, so we're really hopeful he'll be right for the following game."

With fellow key defender Kyle Hartigan also sidelined with a hamstring injury, the Crows have promoted 25-year-old Keath, who was recruited at the start of 2016 as a Category B rookie.

The 198cm, 97kg Keath played seven first-class games and 16 one-day domestic games for Victoria, and five games for the Melbourne Stars in the Big Bash League before switching codes.

"Alex is a really strong competitor, his attack on the ball and his ball use is really efficient as well," Pyke said.

"He's got some speed and some competitive spirit that we like.

"He's performed really well at SANFL level for us and he comes in as a tall defender, and Geelong have some talls down in their forward line."

Sloane still has to pass another concussion test after he was knocked out in the win over the Demons, but the Crows are happy with his progress.

"He'd have to go backwards from here to not play," Pyke said.

The Crows also expect key forward Jenkins to take his spot in the side as he recovers from a bout of food poisoning earlier in the week.

"He's now into the full recovery phase and we're very confident with the time still to game day that he'll be fine," Pyke said.

The Crows have won four of their past five games, but haven't beaten the Cats since 2013.

That includes a 22-point loss at Simonds Stadium in round 11.

"We played them six or seven weeks ago and there are some things we need to learn from," Pyke said.

"I think our recent form suggests we have and we're playing some good footy.

"It's an exciting opportunity to play against a high-quality side in a big game where the stakes are high."