Sharks second-rower Wade Graham said Cronulla's injury-ridden season is starting to catch up with them with the club struggling for consistency in recent weeks.

Graham and teammate Josh Dugan returned on Sunday afternoon but weren't able to help their team to a win over the Sea Eagles, with a Daly Cherry-Evans field goal handing the Sharks a 33-32 defeat at Southern Cross Group Stadium.

With just four weeks until the finals, Graham told pan66.com the team needed to start producing consistent performances.

"We need to find that consistency," Graham said.

"We're up and down, not just week-to-week but up and down in one game.

"It's a crucial time in the year as well which makes it even more disappointing.

"Last week we didn't score enough points and this week we let too many in so it's not just one area we need to focus on."

Match Highlights: Sharks v Sea Eagles - Round 21, 2018

Graham has spent seven weeks on the sidelines due to injury this season, while teammate Luke Lewis has spent 11.

Dugan (knee, foot), Matt Moylan (hamstring), Luke Lewis (foot, calf and hamstring), Paul Gallen (knee), Scott Sorensen (hand) and Kurt Capewell (thumb) have also all spent time in the casualty ward this year, but Lewis remains confident the glimpses of impressive football they have shown will come together for a full 80 minutes in the coming rounds.

"I've been in and out, Wade and Dugan have been the same so we haven't had that chance to be on the field week in week out to understand each other's game," Lewis said.

"We show glimpses of it - we play 10 to 15 minutes of good footy then we'll give it away over a silly penalty or a stupid error coming out of our end. We need to put those minutes together.

"We just need to find our feet and get into a bit of a rhythm.

"If we can do that I think our best footy is in front of us but we haven't got too much time left up our sleeves to nut it out and make sure we get it right before the big games come."

The Sharks head to Melbourne on Sunday to face the Storm, who are also chasing a win after the Rabbitohs defeated them 30-20 last Friday night to claim first spot on the ladder.

Top 5 Plays of the Week – Round 21

Lewis said Cronulla needed to step it up several notches to compete with a strong Melbourne outfit.

"Our disciplines weren't spot on against Manly and just giving up silly errors at silly parts of the field," Lewis said.

"We have a tough one coming up against Melbourne so we need to be 10 times better than what we were against the Sea Eagles."