AUGUSTA, Ga. — Phil Mickelson was already in the air.

With storms in the forecast, he left as soon as he was finished playing to fly back home to California with his wife, Amy.

But Mickelson knew the significance of what was about to take place. Tiger Woods was going to win the Masters in April 2019, win it for the fifth time in a career that was halted in its tracks by a series of back injuries and off-course scandal and looked like it may never again produce moments like what was about to take place.

So, Mickelson’s last act before leaving the golf course for the airport — with Woods still making birdies on the back nine — was to scrawl a message in black Sharpie on an Augusta National Golf Club logoed cocktail napkin and pin it to Woods’ locker in the Champions Locker Room.

It read: “Tiger, so impressive! What a great tournament you played! So very happy for you! Phil’’

You’d never know these two were once bitter rivals with a frosty relationship — when Woods was winning his first 14 career majors and Mickelson was playing the frustrated bridesmaid.

Now, with eight Masters titles between them, they are two superstars of their sport in transition.

Woods and Mickelson are making the slow, steady and inevitable move from being tournament favorites to becoming ceremonial Masters past champions who come every year to soak in the week like jovial old-timers exchanging stories at the annual Tuesday night Champions Dinner.

Make no mistake: They’re both at Augusta National this week with eyes on winning again — Woods in pursuit of a sixth green jacket to tie Jack Nicklaus for the most all time and Mickelson trying to match his idol, Arnold Palmer, with a fourth.

But Mickelson is 50 now, 10 years removed from his last Masters win and having just recently dabbled in his first Champions Tour events (winning both), and Woods is 44.

Before our disbelieving eyes, Woods has gone from cold-blooded killer to wistful father of two with a receding hairline. He looks more like his father, Earl, every day.

Woods nearly talked himself into tears in his pre-tournament press conference Tuesday while recounting the emotionally charged moment when he saw his kids off the 18th green after he won that 2019 Masters. His voice quivered and he conceded to getting “a little teary’’ when merely thinking about the moment.

Woods used two phrases that stood out like the red shirts he wears on tournament Sundays. He talked about winning his first Masters in ’97 and hugging his father on 18 and then last year hugging his son, Charlie, and used the phrases “full circle’’ and “pretty good bookends.’’

This is the same player who used to glare at you if you asked him what his expectations were for the week and deliver a cold one-word answer: “Win.’’

How about this week as defending champion?

“Do I expect to contend?’’ Woods said. “Yes, I do.’’

The word “contend’’ used to be an insult to Woods.

Woods then referenced Nicklaus tying for sixth in 1998 when he was 58, Bernhard Langer, entering the final round in 2016 tied for third at age 58, and his friend, Fred Couples, tied for the lead through 36 holes in 2012 at age 52.

“It can be done,’’ Woods said. “This is a golf course in which having an understanding how to play and where to miss it and how to hit the shots around here, it helps.’’

Mickelson seconded that notion.

“I think that if there’s ever a course that I was going to compete on, it would be this one, because you don’t have to be perfect,’’ Mickelson, always the perfectly imperfect player, said. “This course gives me as good a chance as any golf course. I just need to play it aggressively and execute.’’

Both players, though, recognize the steep pitch of the mountain they’ll have to climb to win this week.

While it doesn’t seem long ago that they were the top dogs in the Masters fields, now it’s all about Bryson DeChambeau and his chase to change the game, Rory McIlroy and his pursuit to complete the career Grand Slam, Dustin Johnson and the validation of his No. 1 world ranking, Justin Thomas and newcomers Collin Morikawa and Matthew Wolff … and on and on.

“I’m not going into this event thinking about winning,’’ Mickelson said. “I’m going into this event thinking about trying to get into contention for the weekend and then hopefully take it from there.’’

That’s surely the approach Woods took 19 months ago, and look where it got him.

“I think it provides a little bit of inspiration for a lot of us,’’ Mickelson said. “I thought that it was one of the greatest feats in the history of sports … one of the greatest feats of all time.’’