Declared a long shot even to play, Melbourne’s injured halfback Cooper Cronk delivered his best performance of the NRL season as he steered the Storm to a 24-6 win over Penrith.

On the eve of the AAMI Park match, Melbourne coach Craig Bellamy said he “couldn’t imagine” Cronk being fit to back up after playing in Queensland’s State of Origin win on Wednesday night on a badly injured ankle.

But a determined Cronk didn’t let the damage affect him as he set up three Storm tries and then scored one himself for his team to leapfrog Cronulla, who play Canterbury on Monday night, and go top of the ladder.

Melbourne’s skipper Cameron Smith was also returning from Origin, as were Panthers backs Matt Moylan and Josh Mansour.

Winger Mansour started well with an early try for a 6-0 lead but the Storm duo dominated their opponents, with their kicking game key to the victory.

They combined to put prop Jesse Bromwich through in the 18th minute and then Cronk found Kevin Proctor on the charge on the back of a Smith 40-20.

Melbourne’s third try was scored by mid-season recruit, former Parramatta player Ryan Morgan, who pounced on a Cronk grubber in the 33rd minute to set up the 16-6 halftime lead.

Although it was only 10 points, the Storm still looked well in control of the match.

They didn’t add to their tally until the 66th minute when Panthers lock Isaah Yeo was penalised for a high shot on Storm five-eighth Blake Green, with Smith pushing the lead out to two converted tries.

Cronk capped the night when he snatched a ball after a Nelson Asofa-Solomona break to dash 30 metres to touch down.

It was Melbourne’s sixth straight victory while Penrith have lost their past two.