The Sydney Roosters are one game from the NRL grand final after defeating a gallant and luckless Cronulla 21-12 at Allianz Stadium.

The minor premiers delivered a complete performance on Saturday night with magic man Cooper Cronk icing the game when he booted a field goal seven minutes from fulltime.

The Sharks were struck an early blow when they lost backrower Wade Graham to what appeared to be a serious knee injury.

Shane Flanagan’s side will now return to Allianz Stadium on Friday night to meet Penrith in an all-or-nothing semi-final.

Despite the loss of Graham, the Sharks never gave up but were guilty of blowing two rolled gold chances with Ricky Leutele and Josh Dugan coming up with key errors in try-scoring situations.

Luke Lewis also looked certain to score when he grasped a Chad Townsend kick only to drop the ball over the line after a desperate try-saving tackle from Latrell Mitchell.

From there, the Roosters raced up the other end of the field and Cronk booted the one-pointer to leave him on the verge of qualifying for his third grand final in three years.

After the Roosters carried a four-point lead into the second-half, the Sharks edged in front when Edrick Lee swooped on a deft Townsend grubber and Valentine Holmes booted the extras from the sideline.

The Roosters re-gained the lead when Daniel Tupou flew high to bat-back a Cronk bomb into Mitchell’s hands and from there the Roosters ran home with it.

Sharks halfback Townsend was on the end of a dubious knock-on call 10 metres out from his own tryline and the next set James Tedesco sent Tupou over to make it 18-12.

The black, white and blue had reason to protest after Tedesco’s last pass also appeared forward.

Earlier, Graham produced a skilful late offload to send Feki over in the corner for first points in just the fifth minute.

However he was taken off the ground just eight minutes later when he appeared to twist his right knee trying to clean up a Cronk grubber.

The Sharks back-rower coughed up the ball, allowing Cronk to regather and score, before being taken off.

Roosters centre Mitchell has a nervous wait after slamming Josh Dugan to the ground in a grapple tackle early in the second half and he will on Sunday come under the scrutiny of the match review committee.

While he wasn’t put on report, the NSW Origin star has 75 carryover points and will miss game time with any charge.

Panthers players celebrate a try. Photograph: Brett Hemmings/Getty Images

Earlier in the day, James Maloney cemented his status as a finals specialist after leading Penrith to a decisive 27-12 win over the Warriors and book a semi-final date with the Sharks.

Maloney was at the forefront as the Panthers took full advantage of a first half injury to Warriors captain Roger Tuivasa-Sheck on Saturday - a setback his teammates could not overcome.

The Warriors were down by two when fullback Tuivasa-Sheck was assisted from the field on the half-hour mark after suffering a suspected medial ligament injury.

Panthers centre Tyrone Peachey nabbed his second try a minute later and from then on Penrith were on track for their third straight semi-final appearance.

While Tuivasa-Sheck’s exit effectively ended any hope of the Warriors’ first foray in the finals since 2011 - and it was Maloney who stepped up when it mattered for the Panthers.

The two-time premiership-winner has played in the eight of the past nine finals series, showed all his experience to the 17,168 crowd at ANZ Stadium.

“He knows what to do in each moment so it’s like having another coach out there,” said Panthers coach Cameron Ciraldo.

“I thought the whole week he’s shown some really good leadership qualities.

“I felt that a couple of weeks ago you could see his intensity go up, he really rallies the troops. He’s born for this time of the year and we’re really lucky to have him on our side.”

The Warriors had raced to a 12-2 lead inside 14 minutes courtesy of tries to Issac Luke and David Fusitu’a, who equalled Francis Meli’s club record of 23 tries in a single season.

His team under the pump, it was Maloney’s attempted 40-20 that resulted in Peachey crossing not long after.

Maloney made it two tries in three minutes when Luke’s kick-off went out on the full.

Tuivasa-Sheck’s injury then tilted momentum heavily in the Panthers’ favour, and it showed on the scoreboard as Peachey got his second moments after the Warrior’s departure.

Panthers winger Christian Crichton made it a two-try lead not long after halftime, and with the Warriors’ spirits dwindling, Maloney put the nail in the coffin with a 60th minute field goal.

In contrast, Warriors star Shaun Johnson was noticeably quiet, while the defeat also marked a subdued end to veteran Simon Mannering’s 301-game career.

Warriors coach Stephen Kearney lamented Tuivasa-Sheck’s injury, fundamental errors also allowed Penrith to pile on 25 unanswered points.

“When Roger came off there was a bit of a lull I thought in our energy, so that didn’t help and we just didn’t find any momentum in that second half,” he said.

