Crows defender Brodie Smith will likely join Adelaide's injury list, putting a further dent in the club's backline stocks.

Smith is in doubt for the Crows clash against the Bombers on Friday night. The 32-year-old is a chance to join fellow backman Jordon Butts, who has been ruled out injured with a hamstring concern.

Smith was on a reduced load at Thursday's captain run due to back soreness.

"(He was) just a little bit sore from the weekend so it was a light session for him," coach Matthew Nicks said of Smith, via the AAP. 

"We're hopeful he will be fine, we're reasonably confident."

James Borlase, who has only six games under his belt, will fill Butts' fullback position on Friday. Smith has not been officially ruled out but is in serious doubt after not getting through Thursday's session.

ADELAIDE, AUSTRALIA - FEBRUARY 04: James Borlase of the Crows kicks the ball during an Adelaide Crows AFL training session at West Lakes on February 04, 2021 in Adelaide, Australia. (Photo by Daniel Kalisz/Getty Images)

Key defender Daniel Curtin, who the Crows picked eighth overall in last year's draft, will remain in the SANFL this week and will continue to wait for his AFL debut. Unless Smith can't get up, the youngster could potentially get a late call-up.

"You're never that far away ... he's playing some good footy at SANFL level," said Nicks.

"There is no rush from our point of view to throwing him in, but we're pleased with how he's developing.

"Before you know it, we will be sitting here talking about Dan and ... I am confident he will play footy this year at AFL level."

Veteran Rory Sloane still has no date on his return after eye surgery.

"He's just working his way through now the physical and mental side of what is getting back into footy," Nicks said.

"There will be no time frame put on that from our point of view.

Rory Sloane during the AFL match between Essendon and Adelaide, Round 4, 2022 (Photo by Cameron Grimes / Zero Digital Media

"He's a champion at this footy club and we'll make sure that he's able to make that decision in his own time."

Adelaide host Essendon on Friday night at Adelaide Oval. With many Crows players out injured and Smith now in doubt, Nicks is going to have his hands full come the clash.