ANOTHER setback in Richmond ruckman Shaun Hampson's recovery from a back injury could see him miss the rest of the year.

Hampson, 29, struggled through the pre-season with the complaint and was placed on the long-term injury list in March.

Tigers coach Damien Hardwick said on Friday he didn't know exactly how long Hampson would be sidelined for.

"He had a setback, I think it was last week again," Hardwick said.

"Unfortunately with backs, you're never quite sure how they're going to respond. He'll be moving well and then all of a sudden something won't feel right and he'll go back a little bit.

"It's going to be longer than we initially thought, how long we're not too sure."

Hampson has turned to pilates to improve his weaknesses.

"It's always in the back of your mind that it's one of those ones that might hang around for 12 months," Hardwick said.

"He's doing a power of work on some areas that are a little outside the square.

"He's doing a lot of pilates off-site. We're just saturating him with that at the moment, just to try and get a bit of stability around his back and pelvis area."

Hampson is contracted until the end of 2018 and is stranded on 98 games.

In his absence, Toby Nankervis has asserted himself as the club's No.1 ruckman.

Fellow big man Ben Griffiths will have an extended break suffering more than five concussions throughout his career, the most recent of which occurred in the VFL last Saturday. Richmond football boss Neil Balme has said the hit wouldn't have injured most players.

"We're still very confident with Ben that he'll be available to play at some stage this year. We'll give him an extended break just to make sure we tick all the boxes with that," Hardwick said.