Sharks lock Paul Gallen.

Flanagan fears Gallen may miss GF qualifier

Cronulla Sharks coach Shane Flanagan fears inspirational skipper Paul Gallen could miss next week's grand final qualifier against the Storm after suffering a rotator cuff injury in the narrow 21-20 win over Penrith at Allianz Stadium on Friday night.

Gallen landed awkwardly on his shoulder after attempting a tackle on Dallin Watene-Zelezniak in the 48th minute and was unable to lift his arm above his head after the game.

Flanagan knows how tough his skipper is and the fact he did not return to the field after getting hurt has the coach worried ahead of the daunting trip to AAMI Park.

"Gal will get a scan in the morning or maybe tonight if we can get one - touch wood that he's OK but it's a bit unknown," Flanagan said.

"If Gal doesn't come back on I'm real concerned - he usually can just go in and get it strapped up and battle on but for him not to come back in a big semi-final was a bit concerning.

"Let's hope it's not as bad as first thought."

Speaking to Channel Nine after fulltime, Gallen was not exactly confident of his recovery chances.

"It's my rotator cuff, I haven't got any movement or strength in it at the moment," he said.

"I don't know exactly what it is but not too good at the moment.

"I couldn't go back on. I couldn't even lift my arm above my head. Fingers crossed it settles down in the couple of days but not too good tonight."

Another of the Sharks' forward leaders, Luke Lewis, joined Gallen on the sideline in the 62nd minute after tweaking his calf but he is expected to be OK for next week.

Centre Josh Dugan, who was ruled out of the Panthers game with a shoulder injury, remains a 50-50 proposition to travel to Melbourne.

"Lewie's had calf tightness for a while, he should be OK," Flanagan said.

"(Josh will train on Monday and hopefully it will be OK.

"He was close but he couldn't do the contact that we wanted him to do on Thursday so it's probably 50-50 again I would say."

After dominating the first half to lead 18-2 at the break, the Sharks were on the end of a trademark Panthers comeback and Flanagan admitted to a touch of panic midway through a pulsating second term.

"I thought in the first half we executed really well," Flanagan said.

"At halftime I was happy with our performance but in the second half they got some momentum, we couldn't get out of our end and possession swung.

"We were ready to be knocked out about the 20-minute mark I thought.

"But we just hung on and showed some real grit and found a way to win."

The Sharks head south safe in the knowledge that they beat Cameron Smith's men 17-14 at AAMI Park in round 22 and also knocked off the premiers in round four.

"We've had some great tussles with them, obviously from the 2016 grand final and the last couple of years they've been fantastic games - we've been lucky enough to win some and unlucky on a couple of occasions or they've been too good for us," Flanagan said.

"It's a real challenge going down there on the back of Melbourne having a week off.

"They'll be fresh, they'll have some players back from suspension and injury so we'll have to be on our game if we are going to play in the grand final."