Rocco Mediate and Tiger Woods will come back on Monday for an 18-hole playoff to decide the US Open after the world No.1 drained a 20-foot putt on the final hole at Torrey Pines. Mediate, 45, was all set to become the oldest first-time major winner in history after holding his nerve in a tense final round battle with Woods and Lee Westwood (73). But Woods, who had been frustrated throughout his even-par final round, saved his best effort for the last hole, rolling the ball into the cup to book a tee time with Mediate (71) on Monday. The world No.148 showed no nerves late in a tense final round, sharing laughs with the gallery down the final few holes. In contrast, Woods looked to be struggling in his first tournament since he underwent knee surgery after the US Masters, but was all smiles after his 72nd-hole heroics. Woods, who held a one-shot lead overnight, made a terrible start with a double bogey at the first and a bogey at the second to surrender the lead. The world No.1 then had to wait until the ninth hole to pick up a shot, but when he bogeyed the 11th and Westwood bogeyed 10 and 12 he found himself in front. But Mediate, playing in the group ahead of Woods, had overcome his jitters on the front nine where he carded back-to-back bogeys, to pick up shots at 10 and 14 to take the lead. Westwood closed within one with a birdie of his own at 14 after Mediate bogeyed 15. But Woods also bogeyed 15 to slip back level with his playing partner. Mediate was solid down the final three holes, putting the onus on Woods and Westwood to catch him. Woods narrowly missed a birdie putt on the penultimate hole, while Westwood made a clutch par putt to stay in the hunt. Both players found bunkers off the 18th tee but had medium range putts to send the tournament into a playoff. Westwood left his short, but Woods&apos ball never looked like missing. Robert Karlsson (71) and DJ Trahan (72) finished on two-over in a share of fourth, while Miguel Angel Jimenez (72), John Merrick (72) and Carl Pettersson (68) shared sixth on three-over. Geoff Ogilvy, who bogeyed the fourth, had his chances and moved close to the lead when he collected two birdies at five and seven. But back-to-back bogeys on nine and 10 robbed him of crucial momentum and when he bogeyed 16 he was forced to watch the battle for victory from afar. He would also bogey 17 to finish in a tie for ninth with Eric Axley, Heath Slocum, Brandt Snedeker and Camillo Villegas. Rod Pampling was the next best placed Australian on five-over and in a tie for 14th after a final round 70 which included a bogey and two birdies. Robert Allenby was another shot back after failing to make the most of his strong first three rounds with a four-over round of 75. Adam Scott&aposs 70, his best effort for the week, saw him grab a share of 26th on plus-seven, one clear of Aaron Baddeley, who signed off with a 74 on what was a solid week. Stuart Appleby, who led this tournament at the halfway stage, continued his disappointing weekend with a final round 75 which saw him finish in a tie for 36th. The only other Australian to make the cut, Jarrod Lyle, ended his week with a 71 and share of 48th on 10-over. Final Round Scores from the USA Open, California -1: Rocco Mediate 69 71 72 71, Tiger Woods 72 68 70 73 E: Lee Westwood 70 71 70 73 2: Robert Karlsson 70 70 75 71, D.J.Trahan 72 69 73 72, Miguel-Angel Jimenez 75 66 74 72 3: John Merrick 73 72 71 71, Carl Petterson 71 71 77 68 4: Eric Axley 69 79 71 69, Geoff Ogilvy (Australia) 69 73 72 74, Heath Slocum 75 74 74 65, Brandt Snedeker 76 73 68 71, Camilio Villegas 73 71 71 73 5: Stewart Cink 72 73 77 67, Ernie Els 70 72 74 73, Retief Goosen 76, 69, 77, 67, Rod Pampling (Australia) 74 70 75 70 6: Robert Allenby (Australia) 70 72 73 75, Chad Campbell 77 72 71 70, Sergio Garcia 76 70 70 74 Also: 7: Adam Scott (Australia) 73 73 75 70 8: Aaron Baddeley (Australia) 74 73 71 74 9: Stuart Appleby (Australia) 69 70 79 75 10: Jarrod Lyle (Australia) 75 74 74 71