As the Storm dropped its second straight game, the veteran left the ground on crutches with coach Craig Bellamy fearing the worst.
“We’re all concerned, he’s in tears in the dressing room,” Bellamy told melbournestorm.com.au.
“He has been a wonderful player for our club, I’m not too sure he will play again, to be quite honest.
“They’re thinking it’s a really major injury. I know he will do everything he can to get back again this year and not have to retire on this note.”
Hoffman has played 324 NRL games, represented NSW 14 times in State of Origin and Australia six times on the international stage.
Hoffman played in the Storm’s 2012 premiership, having also played in both the 2007 and 2009 stripped premierships.