The man known as Jimmy the Jet has been grounded since round three with an achilles complaint but impressed Boyd with his sharpness at Wednesday's Red Hill training session.

Despite being contracted to Brisbane until 2021, Roberts has been linked to a move to South Sydney to reunite with coach Wayne Bennett after cousin Greg Inglis's retirement.

Like teammate Corey Oates on Tuesday, fullback Boyd isn't weighing into the speculation and just wants to see the game-breaker back on the park.

"Hopefully (he'll play against the Raiders); at training he was pretty sharp there today," he said.

"He's (looking) pretty free, the boys were struggling to tackle him there.

"A couple of weeks off probably freshened the body up."

Wests Tigers star Benji Marshall is among those encouraging Souths to chase Roberts, who began his NRL career at the Rabbitohs in 2011.

Kotoni Staggs has performed strongly in the absence of Roberts while Jack Bird is beginning to find form on the opposite side of the field in what could prove a potent long-term centre pairing at Red Hill.

But Boyd admitted Roberts's rare talent would be hard to replace.

"He's an excitement machine; every time he touches the ball he's a chance of doing something special," he said.

Boyd also shut down any suggestion of a move into the halves, backing Anthony Milford and Kodi Nikorima to silence the critics.

Brisbane ran through field-goal scenarios at training on Wednesday, with Boyd admitting they couldn't afford to stumble in the moment like they did in last Thursday's loss to Wests Tigers.

"There was a lot of criticism about last week," he said of the horror set of six that handed momentum back to the Tigers.

"We've got to make sure we get it right.

"In house we're happy with who we have, what we do and what we've got.

"At the end of the day we need to listen to Seibs and the coaching staff, cause they're the voices that matter."

Australian Associated Press