Roosters coach Trent Robinson was left to bemoan a scrappy try to Matt Prior midway through the first half that he believes swung momentum in Cronulla's favour on Saturday night.
The Sharks ran out 37-12 winners to force a showdown for the minor premiership with the Storm in Melbourne next Saturday night, and while it looked like a comfortable victory, Robinson said the 25th-minute try was the turning point.
Prior to the four-pointer, the Tricolours appeared in complete control at 12-0 and looked likely to heap more misery on the Sharks who had been winless in their past four matches.
However, the game took a 180 degree turn with Prior's try, with the Sharks piling on 37 points in 55 minutes to close to within one point of the Storm on the Telstra Premiership ladder.
The Sharks front-rower reacted fastest to a Michael Ennis grubber that was originally spilled by Roosters five-eighth Connor Watson, before it took a deflection off Dylan Napa's legs, to get the Sharks on the board in fortuitous fashion 15 minutes before half-time.
"I thought the scrappy kick we should have picked that up," Robinson said.
"I thought we could have been a try ahead…that would have been nice. But in the end the ricochet try…you've got to clean them up.
"They got a plucky field goal from Jimmy – which was well hit – to get them 13-12 in front, but I thought we were on top.
"The ricochet grubber – I would have liked to have cleaned that up – but the next try was fair enough. They deserved to get back into it.
"We were on top for 25 [minutes] and they were on top for 15 minutes and then ended up in front. That's what the top teams do."
Roosters skipper Jake Friend put in yet another Herculean effort in defence, racking up 70 tackles in the heavy defeat.
Like his coach, Friend was disappointed with his side's second-half performance, but hoped to salvage some pride next week against the Broncos in a replay of the classic 2015 preliminary final.
"The first half I thought we were good, and whilst those late tries were disappointing, I thought we were in it," Friend said.
"The second half wasn't good footy. We didn't get in the arm wrestle and we didn't find any rhythm in that second half and the Sharks took advantage of that.
"We've got 80 minutes next week to put it out there again and take whatever we can out of this season."
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