St George Illawarra Dragons expect to be without captain Gareth Widdop for around six weeks after he suffered a knee injury during the 13-12 NRL loss to Sydney Roosters on Tuesday.
The talismanic five-eighth will miss England's Test against Samoa on May 6 after damaging his left knee during an Anzac Day thriller at Allianz Stadium.
Widdop was unable to continue as a result of damage done while he tried to escape the in-goal area late in the first half.
The Dragons feared the worst and on Wednesday confirmed Widdop will be out of action until June.
"Gareth has some significant damage to his medial collateral ligament in his left knee." Dragons head of athletic performance Nathan Pickworth said.
"The next two weeks he'll be in a brace, after those two weeks will give us a good indication of his return-to-play timeframe.
"Hopefully it will be somewhere around the six-week mark."
Pickworth was able to offer a positive update on Jack de Belin, who suffered a cut against the Roosters but will be available to face Melbourne Storm on Saturday.
"He's in no doubt for this weekend's game." Pickworth said. "He did have a significant cut, the only thing that's really been damaged there is Jack's thoughts around his good looks!"