Rocco Mediate and Tiger Woods after the end of Round IV of the US Open at Torrey Pines on Sunday. (AP)

La Jolla: He did it again, almost on command, as Rocco Mediate’s heart, and the sun, sank. Tiger Woods, who before the 108th US Open had not walked 18 holes since left knee surgery on April 15, is going to walk at least 18 more. He’s going from a long layoff to a long playoff.

Woods slithered a 12-foot birdie putt into the right side of the cup at No. 18 to pull even with Mediate on Sunday’s 72nd hole and force one extra day of adrenaline at Torrey Pines.

Woods and Mediate finished one-under 283 overall.

Lee Westwood’s two-over-par 73 left him one shot out of the party and sent him home at even-par 284. Robert Karlsson and D.J. Trahan finished three shots back at two-over 286. They are all footnotes now.

Woods had lost the one-shot lead he took into Sunday, struggled to a two-over 72, struggled with his driver and with his putting. But he made the putt he had to make when he had to make it.

The US Open is the only one of the four majors that requires an extra 18 holes to determine its champion, like it or not.

It will be the first US Open playoff since 2001 at Southern Hills, when Retief Goosen defeated Mark Brooks on a Monday in Oklahoma.

Never mind that Woods vs Mediate sets up like Ali vs Wepner.

Woods is 32 years old to Mediate’s 45. Woods has won 13 major championships to Mediate’s none. Woods has 64 PGA tour victories to Mediate’s five.

Upon arrival at Torrey Pines, Mediate had one top-10 finish this year and had missed eight of the first 10 cuts on tour this season. Woods had nine exemptions qualifying him for the US Open. Mediate earned his way in at a sectional qualifier in Columbus, Ohio.

You could sense the playoff coming when Mediate made par five on the finishing hole when birdie would have forced Woods and Westwood to make eagle. Mediate’s hopes were buoyed, though, when Westwood and Woods hit their drives into bunkers, forcing lay-ups on a hole that was reachable in two.

Woods seized his chance with his usual laser-beam stare. Mediate was holed out and holed up inside, adjacent the 18th grandstand, waiting to see whether he was going to get to hoist a trophy or set his alarm clock.

Woods made the putt, of course.

One question leading into the playoff might be: what will break down first over 18 holes: Mediate or Woods’ knee?

Woods has been hobbling all week, wincing after powerful swings, and he’s now on course to play 90 holes in five days.

Was the knee better or worse? “Not better,” Woods said.

What did the doctor say about your knee?

“Don’t play golf,” Woods said.

Instead, Woods has opted for more, pitted against a friend, but a decided underdog, in quest of his 14th major championship.It’s Tiger vs Rocco.