SPRINGFIELD, N.J. — If you thought two weeks was enough time for Phil Mickelson to get over his second-place finish in the British Open duel with Henrik Stenson, guess again.

Lefty said it’s going to take a long time to get over the British Open, probably longer than any of his other excruciating losses in majors.

The hurt and disappointment wasn’t because Mickelson missed out on either his sixth major or his first win since the 2013 British Open. This was the first time the 46-year-old Mickelson played his best, and it wasn’t good enough.

The 40-year-old Stenson won his first major with a record-shattering 20-under total. Mickelson’s 265 final total would have won every British Open other than the most recent one.

‘‘I think it’s one of those things where I’ll look back over time and my disappointment will probably increase, because I think it’s the first time in my career that I have played to that level of golf and not had it be enough to win a tournament,’’ Mickelson said at a practice to prepare for the PGA Championship at Baltusrol Golf Club. ‘‘That’s a disappointing thing because I would have loved to have added another claret jug.’’

Jordan Spieth, who played a practice round with Mickelson on Tuesday, walked over to his playing partner and told him it was fun to watch him, and that he was unlucky not to win.

‘‘And that’s when he said, ‘Hey, I’ve been on that side of things [lately], Masters in ’15, and Troon even more so two weeks ago,’’ Spieth said. ‘‘But then he’s seen himself on the other side of things where no one is running away with it and he wins in a close battle or he wins by a lot, whether it’s in a major or regular tour event.’’

Mickelson believes he will win again. He feels his game is improving, his swing is back and he likes the course. He validated his first major — the 2004 Masters — by capturing the 2005 PGA here with a 72d hole birdie.

His goal this week is to play as well as he did at Troon.

‘‘I don’t believe that there is a small window,’’ Mickelson said of winning again. ‘‘I think there’s a really big window of opportunity to add to my résumé, to continue to compete in big events, for the simple reason that the feel and sensitivity of hitting shots; the ability to play golf courses a certain way, to visualize, to make birdies, to pull shots off, that has not diminished.’’

Mickelson said the key at Baltusrol is to drive the ball straight and putt well on greens that have a lot of contours.

‘‘There’s a lot of little rolls and knolls,’’ said Mickelson, noting the greens are going to roll a lot faster than Troon. ‘‘You can see multiple lines and only one of them is correct, and it’s sometimes hard to see.’’

What many people would like to see would be another Mickelson-Stenson showdown.

Stenson said he has not had a chance to talk with Mickelson since the British Open.

‘‘It’s one of those things, it doesn’t really strike you when you’re in the middle of it,’’ Stenson said.

‘‘But afterward, with the 63 and the 20 under and the way we played, we pushed each other to the limit, both of us, for 36 holes more or less, and trading punches and blows all the way around the golf course for two days. That certainly is what made us play so well.’’

Willett searching

Since winning the Masters, Danny Willett has taken his green jacket to Wimbledon, thrown out the first pitch at a New York Yankees game and enjoyed the celebrity that goes with being a major champion. Add in fatherhood and it’s been a couple of fun months.

Willett’s golf game is another story. He has played in seven tournaments since winning at Augusta and has only one top-10 finish, a third at the BMW PGA Championship in his native England on the European Tour. He tied for 37th in the US Open, finished tied for 53d in the British Open, and missed three cuts.

The goal for this week at the PGA Championship is to get his game going again.

‘‘I think it’s settled down a bit now. We are trying to get back down to work and knuckle down because we have got a very important second half of the season coming up,’’ said Willett, 28, who will play in the Olympics and Ryder Cup this year.

‘‘It’s time to move on a little bit from what we did in April,’’ he said. “It was fantastic but we need to get back to the kind of form that we took into that week and hopefully then move forward.’’

Willett never had a chance in the British Open, simply based on tee time. He had an afternoon draw in the opening round, got the worst of the weather and never recovered.

‘‘You look at the weather conditions were pretty brutal over there,’’ Willett said. ‘‘Rory [McIlroy] was the tee time behind us and I think he finished the best from our side at 4 under, I think. To shoot the scores at the boys shot would have been virtually impossible from the times that we played.’’

The weather — other than the heat — should not be a problem this week. The battle will be to find the fairways on this tree-lined venue and the center of the rolling greens at this course that last played host to the PGA in 2005, when Mickelson won with a 4-under total.

‘‘I think if you finish anywhere near, I don’t know, 6-, 7-, under par, personally I think that would be a very good golf score for four rounds around this golf course,’’ Willett said. ‘‘I could be massively wrong, but from what we saw yesterday, that’s how it kind of sits.’’

As far as Willett is concerned, this might be the best field of the year, and the event is wide open, at least judging by what has happened this year in the majors. He won the Masters as an unknown, even though he was ranked No. 12 in the world.

Dustin Johnson finally broke through at the US Open after knocking on the major door for five or so years, and Stenson won his first major at the British Open with a record score to hold off Mickelson.

‘‘It just goes to show the strength and depth throughout golf at the moment,’’ Willett said. ‘‘Yeah, there is two, three, four, of the best players in the world that are playing some particularly good golf right now. But it just goes to show on a week-to-week basis that if anyone who is really there pitches up with their A game, they have got a good chance of winning.’’

The last player to win the Masters and PGA in the same year was Jack Nicklaus in 1975.