As Phil Mickelson upped his Twitter game, his golf game fell. As the pounds came off, the strokes piled up.

And as last week transpired, not only did Lefty find himself out of the top 50 in the world for the first time in 26 years, he was also without a spot on a U.S. team for the first time since before Tiger Woods won his first U.S. Amateur.

If Mickelson were wont to reflect, this would seemingly be a reasonable time. His 50th birthday is approaching next year. He has kids nearly as old as some of the PGA Tour pros he is trying to beat. And he's gone nine months since finishing in the top 10.

That victory at Pebble Beach in February had us thinking about his chance to compete at the Masters, perhaps complete the career Grand Slam at the U.S. Open, also to be played at Pebble Beach, and to continue his remarkable streak of being part of every U.S. Presidents Cup and Ryder Cup team dating to the first one he was a part of in 1994, when Hale Irwin was a playing captain for the United States in the inaugural competition.

Instead, Mickelson's form fell off after that Pebble Beach win, somewhat shockingly. He was ranked 17th in the world then, but he posted nothing better than a tie for 18th at the Masters the rest of the way. After a tie for 28th at the WGC-HSBC Champions in China, he fell out of the top 50 for the first time since entering late in 1993, settling now at 53rd.

And then a few days later, to no one's surprise, he was not among Woods' four at-large picks for next month's Presidents Cup in Australia.

The last time a U.S. team competed without Mickelson was at the 1993 Ryder Cup, where captain Tom Watson led a team that included Fred Couples, Payne Stewart, Lanny Wadkins and Paul Azinger to victory at The Belfry in England -- the last U.S. Ryder Cup victory in Europe. Also on that team? Raymond Floyd, who is now 77 years old.

Of the 24 teams Mickelson played on for the United States (12 each for the Presidents Cup and Ryder Cup), he required a captain's at-large pick just three times -- at the '94 Presidents Cup, the '15 Presidents Cup and the '18 Ryder Cup. Or, 21 out of 24 times, Mickelson made the team on points.

"I just haven't played well,'' Mickelson said in China, while also noting that he didn't deserve to be picked for the Presidents Cup team. "Just had a lot of stuff going on, and I just haven't been really focused and into the mental side. I haven't seen good, clear pictures. I haven't been as committed and as connected to the target. I just haven't been mentally as sharp the last six, eight months.''

Mickelson declined to go into details, suggesting it was more mental than physical, and that he expected to get his game together and compete for a U.S. Ryder Cup team spot in 2020.

And while his form of late has been jarring, it does shine a bright light on the underappreciated nature of his career that has seen him win 44 times on the PGA Tour -- with 35 of those victories coming in the Woods professional era.

To never once fall out of the top 50 since getting there on Nov. 27, 1993, is a remarkable achievement. It doesn't take much, as Mickelson is showing right now. A few months of poor play, a nagging injury, family issues. Any or all of that can derail that lofty ranking.

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Mickelson, himself, has endured his own struggles to remain atop the game. He's had numerous personal issues, including his wife Amy's difficult pregnancy in 2003 and her breast cancer diagnosis in 2009. He's had his own health issues, including psoriatic arthritis. He's had off-the-course distractions that included insider trading charges.

Then there have been the golf-related issues, including the driver problems and swing coach changes (Rick Smith, Butch Harmon, Andrew Getson) that can undoubtedly lead to slumps.

And yet, he remained among the top 50 for 1,353 weeks. The best streak now belongs to Rory McIlroy, 30, who has been in the top 50 for 11 years. He needs only 15 more to match Mickelson.

For 20 years, that distinction has been an important benchmark in the game. It helps determine exempt status for the major championships and World Golf Championship events.

While Mickelson -- as a past winner of the Masters, PGA Championship and The Open -- will have spots secured in those tournaments (even the U.S. Open should not be an issue), he would undoubtedly get a special exemption from the United States Golf Association if he were to fall outside of the top 60 by the two cutoff dates prior to Winged Foot in 2020.

The WGCs are another matter. As Woods knows, past success does not guarantee future performance. Starting in 2015, after back problems sidelined him for long periods, Woods found himself unable to play in the WGCs. He didn't qualify again until the 2018 WGC-Bridgestone Invitational -- doing so by barely cracking the top 50 at the deadline after a tie for sixth at The Open.

Mickelson, for example, would need to be in the top 50 by Feb. 17 to be eligible for the WGC-Mexico Championship -- which he won in 2018.

It will be strange for Mickelson to not be part of the U.S. team in Melbourne next month and would be even more so to see him sitting out a World Golf Championship event because he is not eligible.

To his credit, Mickelson has tried to keep things loose with his self-deprecating humor on Twitter as well as the weight-loss program that has seen him drop more than 25 pounds since July and that he believes will put him on a path to better golf.

"I intend to come back strong, play well and get back on the Ryder Cup team next year,'' he said.