Los Angeles — Phil Mickelson nearly blew the biggest lead of his career, then had to scramble for par to avoid a playoff.

When his roller-coaster week at Riviera ended Sunday, the Northern Trust Open turned out to be one of his most satisfying victories.

After watching tee shots sail in every direction, turning a four-shot lead into a two-shot deficit with three holes to play, Mickelson recovered with back-to-back birdies and stepped to the 18th tee with a one-shot lead.

Then he had to bury some demons.

Two years ago, Mickelson had a one-shot lead until making a sloppy bogey on the historic finishing hole and losing in a playoff. This time, he poured his tee shot down the middle of the fairway and two-putted for par from 60 feet, making a tough six-footer for the victory.

“I’ll take a lot out of this,” Mickelson said after closing with a 1-over 72. “To be able to heart it out on 16 and 17 with two birdies, then to make that par on 18 when two years ago I didn’t, that meant a lot to me.”

So ended his West Coast slump.

Mickelson arrived at Riviera having failed to crack the top 20 in his first three tournaments, missing the cut in Phoenix and making it on the number with a birdie on the last hole at Pebble Beach.

But when one of his wildest weeks was over — 63-72-62-72 — Lefty won for the 35th time in his career, with 17 of those victories on the Left Coast.

He finished at 15-under 269 and joined Ben Hogan, Corey Pavin and Mike Weir as the only back-to-back winners at Riviera.