Phil Mickelson ended his near five-year victory drought with a playoff win over red-hot Justin Thomas in a high-octane WGC-Mexico Championship and revealed his delight at getting a win before the Masters.

Without a win since he claimed the Open Championship at Muirfield four years and seven months ago, the left-hander (47) clinched his 43rd PGA Tour victory with a par-three at the first extra hole as Thomas — bidding for back to back wins — flew the green and failed to get up and down.

"As I said earlier, I needed to get a win before Augusta so that I wasn't trying to win for the first time in four and a half or five years at that event," Mickelson said. "It certainly boosts my confidence." 

It was a thrilling final day at Club de Golf Chapultepec as Thomas followed a three-putt bogey at the 17th by spinning a wedge back into the hole from 119 yards for an eagle two at the 18th to add a 64 to his third round 62 and set the target at 16-under par.

There were still thrills and spills to come as Tyrrell Hatton eagled the 15th and Mickelson birdied the 15th and 16th to tie with Thomas on 16-under-par.

But not only did they fail to birdie the 18th for the win, the Englishman made bogey for a 67 and a share of third with Spain's Rafa Cabrera Bello after a 67 as Mickelson made seven birdies in a swashbuckling 66 that suggests that he will be a force at Augusta National in a month's time.

"This is a very meaningful win,” said Mickelson. “I can't really put it into words, given the tough times over the last four years, and the struggle to get back here and knowing that I was able to compete at this level but not doing it, and the frustration that that led to. To finally break through and to have this validation means a lot to me.”

The veteran moves up 16 places to 18th in the world — Rory McIlroy fell two spot to 12th as Tommy Fleetwood rose to 10th and Sergio Garcia to 11th — and when asked if he was now thinking of getting to 50 PGA Tour wins, he was more than confident.

“Oh, I will,” he said. “I’ll get there."

He added: “I know how great the young players are, I appreciate their skill level. I also know the level I'm able to play, and I'll get there.”

He mentioned Rory McIlroy in a name check of all the great young players and while the Co Down man refuses to put himself under pressure to win before the Masters, Mickelson underlined the importance of going to Augusta without the added pressure of trying to make a major your first win in a prolonged period of time. 

"I knew it was going to happen. I didn't know if it would be this week, I didn't know if it would be today. But I had confidence it was going to happen," Mickelson said.

"It means a lot to me to do it now, especially before Augusta."

Later, he said: "It's important, I think, to have a win in a tournament, especially a big tournament like a World Golf Championship, before the majors because you don't want to feel that type pressure coming down the stretch of a major having not won in a while. You want to remember what it feels like to win.

"And making those putts on 16 and hitting some of the putts I hit on 17, even though they didn't go in, those are shots I will look back on and get momentum from, heading into the big majors and events. This was an important week." 

Overnight leader Shubshankar Sharma headed home for this week's Indian Open after shooting a 74 to finish tied ninth on 10-under, but Paul Dunne's next start may not be until April's Spanish Open in Madrid.

He struggled from the tee all week and closed with a level par 71 to finish tied 55th on seven-over, picking up $58,000 and enough world ranking points to rise five places to world No 81

With no events scheduled, he now needs a sponsor's invitation for a PGA Tour event if he's to have any chance of making the top 64 in the world who contest the WGC-Dell Technologies Championship in three weeks' or the top 50 who will be exempt for the Masters.

On the European Tour, South Africa's George Coetzee produced a sensational mid-round purple patch with the putter to win the Tshwane Open and his fourth win on African soil.

Having grown up at Pretoria Country Club, Coetzee (31) had just ten putts in eight holes from the sixth, making five birdies to open up a three-shot advantage en route to a four-under 67 and a two-shot win over England’s Sam Horsfield on 18-under par.