RICHMOND has suffered a cruel double blow, with recruit Chris Knights ruled out for the rest of the season with a patella tendon injury and fellow midfielder Shane Tuck also facing two months off.

Knights had surgery on Sunday to repair his right knee, an injury he sustained during the second quarter of Saturday’s win over Port Adelaide.

Tuck is set to miss the next six to eight weeks with a fractured scapula, after hurting himself during the third quarter of the contest against the Power. He played out the game but will have surgery on Monday.

Richmond general manager of football Dan Richardson said the news was disappointing.

"It’s realty disappointing for Chris.  He’s been a great addition to the team since arriving at the club late last year, and he’ll be missed on the field," he said.

“I’m sure the players will get right behind him and help him through his rehab, and we’re looking forward to having him back next season.

“Shane is a much-loved figure at the football club, and his courage cannot be questioned.

"We expect him to have a big impact in the senior team in the second half of the season."

In better news for the club, the Tigers should regain Ty Vickery from concussion for Sunday’s match against Melbourne, while Trent Cotchin, Dylan Grimes and Ricky Petterd will be assessed throughout the week.

Meanwhile, Port Adelaide released a statement late on Sunday saying it was aware of a spectator complaint against a fellow fan who allegedly abused Knights as he was stretchered from AAMI Stadium.

"The club has not received an official complaint directly from the spectator but is aware of the complaint via social media," the statement read.

"The club is disappointed with the allegation and is taking the matter very seriously.

"An investigation into the matter will be conducted and the club will make no further comment until that investigation is complete."