HARLEY Bennell's immediate playing future is back under a cloud after the injury-plagued Fremantle star sustained "mild tightness" in his calf while playing for Peel on Saturday. 

The luckless Docker was making his fourth consecutive appearance for the Thunder after his last calf setback in February.

Bennell had eight disposals and two marks before coming from the ground, reportedly before half-time, and he sat out the rest of the match.

The Dockers confirmed to AFL.com.au that Bennell felt tightness and will be assessed in the next 24 to 48 hours.

The development comes as the 25-year-old was closing in on his second coming for the Dockers.

After being traded to Freo at the end of 2015, Bennell finally made his debut for the club in round 22 last year and also played the final game of the campaign before sitting out WAFL finals.

Dockers coach Ross Lyon said this week he was crossing his fingers a new training regime featuring ballet physiotherapy had solved Bennell's soft-tissue problems.

"We're holding our breath and he's working incredibly hard. The ballet (physiotherapy) has topped up his program nicely," Lyon said on 6PR on Tuesday.

"He feels as settled and as strong as he's been since he walked through the door, so that's exciting for our members and fans." 

Bennell took a major step forward last Saturday at East Fremantle when he moved into the midfield and covered plenty of territory, picking up 16 touches and kicking a goal in wintry conditions.

"He played a half-and-a-bit (for Peel) but punched out two-thirds of an AFL game run," Lyon said.

"He'll keep building and whenever we think it's safe for him to play for the team, that he can produce the run required and it's safe for him, and he's in form, all those things ticked off – he would play.

"So there's a few weeks to go yet."

Bennell has played 83 games and kicked 95 goals since making his debut for Gold Coast in 2011.