After giving up an 18-point lead to be back level late in last night's NRL semifinal, the Cronulla Sharks went ahead again with a late Chad Townsend field goal and held on to eliminate the Penrith Panthers.
The Sharks totally dominated the first half, scoring three tries to lead 18-0 just before the break. But the Panthers scored three tries of their own in the second spell to level the scores at 20-20 heading into the last 10 minutes.
But just as Penrith threatened yet another sensational turnaround, Cronulla held their nerve, regained the lead by the narrowest of margins and closed out the semifinal.
Penrith's James Maloney and Nathan Cleary, lauded for their dominant display in a 27-12 win over the Warriors last weekend, were completely outplayed by their Cronulla opposites Matt Moylan and Townsend in the first half.
But if there was one team to overturn such a sizeable margin, it was the Panthers, having beaten the Sea Eagles this season from 18 points down and pulled off three other comebacks from 14-point deficits.
Cleary got the Panthers back in the match eight minutes after the break when he chased hard to dive on the ball just before the dead ball line as Valentine Holmes failed to shepherd it out.
Penrith enjoyed long spells of possession deep in Sharks territory and second rower Isaah Yeo barged through two tacklers near the tryline one out from dummy half to increase the nerves of the Cronulla contingent.
Two minutes later, Viliame Kikau broke the Cronulla line and ran 50m before passing to Waqa Blake, who ran 10m to score. Cleary converted and the Panthers had pulled off an 18-point comeback to level the scores with 11 minutes remaining.
Then came a spell of Cronulla domination which culminated in a Townsend field goal edging his side ahead 21-20 with six minutes left. The Panthers engineered two field goal attempts in the dying minutes but Cleary missed both, including an awful effort from halfway right on fulltime.
Penrith ultimately paid the price for yet another poor start, as Cronulla controlled almost the entire first half. Townsend opened the scoring in the fifth minute, taking a short inside pass in the tackle from Andrew Fifita, the NRL's leading offloader.
Cronulla continued to dominate and were rewarded with a penalty and then a second try 10 minutes after their first scored by Holmes after Sosaia Feki soared high to pat back a Moylan bomb.
Luke Lewis was put into a gap by Moylan and ran in Cronulla's third on the half hour to cap an industrious display.
Penrith finally got on the board with a Cleary penalty right on halftime, a rare positive for the Panthers who trailed 18-2 at the break.
The Sharks advance to next Saturday's preliminary final against the Roosters for a place in the grand final. The Rabbitohs and Dragons meet at Sydney's ANZ Stadium tonight at 9.40pm, with the winner to take on the Storm next Friday.
Sharks 21 (Chad Townsend, Valentine Holmes, Luke Lewis tries; Holmes 2 cons, 2 pens, Townsend field goal).
Panthers 20 (Nathan Cleary, Isaah Yeo, Waqa Blake tries; Cleary 3 cons, pen).