Scans on Monday confirmed Moylan suffered a grade-two hamstring tear chasing Corey Thompson in the Sharks' win over Gold Coast on Saturday.

The 29-year-old was in pursuit of Thompson midway through the first half only to pull up mid-stride and limping off the ground soon after.

"While how the injury responds to treatment will have a bearing on his recovery time, Moylan is expected to be missing for around a month," the Sharks said.

It is yet another setback for the one-time Kangaroos representative, who has been dogged by hamstring problems for over two years.

Limited to just 11 games last year, Moylan has also missed three of a possible nine games so far this season due to calf and hamstring concerns.

His horror injury run prompted NSW State of Origin legend Andrew Johns to recently question Moylan's long-term future in the game.

The diagnosis comes with Cronulla in their best form so far this season, having won three straight games to be on the cusp of the top eight.

Former Blues star Josh Dugan is likely to wear the No.1 in Saturday's crunch clash with Penrith, having filled in while Moylan was injured against the Titans.

Coach John Morris has another option in Will Kennedy, who has played five games at fullback so far this season after debuting last year.

Cronulla also revealed winger Ronaldo Mulitalo is a chance of returning from a knee injury to face the Panthers.

Australian Associated Press