ADELAIDE forward Josh Jenkins is extremely doubtful for Saturday night's Showdown with Port Adelaide at Adelaide Oval.

Jenkins was restricted to jogging laps at the Crows' main training session of the week at Football Park on Wednesday morning.

The 28-year-old suffered bruised ribs in the opening quarter of last weekend's win against Hawthorn at the MCG. 

He was taken to hospital, but was cleared of any structural or internal damage.

Crows assistant coach Scott Camporeale said Jenkins would be given until the last minute to prove his fitness. 

"We'll give him every opportunity up until the morning of the game," Camporeale told reporters on Wednesday. 

"He's obviously an important part of our forward line, so we'd be silly to rule him out early. 

"He jogged some laps today, he seemed in a bit better shape today, so we'll take it day by day. 

"We need to see him train at match intensity and (see) some of his contest stuff."

Along with playing a key role in attack, Jenkins also serves as the back-up ruckman for the Crows to help out Sam Jacobs. 

Andy Otten filled that role admirably against the Hawks when Jenkins left the game, while Reilly O'Brien – who played two games last season - is another option to come into the side. 

The Power boast a formidable ruck combination with the athletic Patrick Ryder getting support from Jackson Trengove and Charlie Dixon. 

"We're still a little bit undecided," Camporeale said. 

"We'll have a look at what the balance looks like versus what Port will throw at us. 

"It's always an interesting one at match committee, whether you play two genuine rucks versus a Jacobs who plays big minutes and we have a pinch hitter. 

"It's always a week-to-week conversation. 

"It really depends on how we want to structure our forward line. 

"A forward line without (captain Taylor Walker) and (Jenkins) at times has worked really well, so there's an opportunity to maybe expose Port from a forward perspective as well if we go a bit smaller." 

Jenkins is the only injury concern for the unbeaten Crows ahead of their clash with the ladder-leading Power.

Defender Jake Lever trained with the main group as he pushes his claims for a recall to the senior side. 

Lever missed the JLT Community Series with a hamstring injury, but has regained match fitness with two games with the Crows' SANFL team.

"Jake's done a lot right to get back to where he is, he's had two games in the SANFL and he's been our best player both times," Camporeale said. 

"I would suggest there would be a strong case for him to play this week."