Leaner Tiger Woods and Phil Mickelson, ‘dialed in’ Dustin Johnson prepping for 2015

Tiger Woods, Phil Mickelson, and Dustin Johnson are hitting the gym, the practice range, and, in DJ’s case, the bike trail, as they set their sights on a healthier, more successful, and in Lefty’s case, “great” 2015.

Woods, who’ll be the first of the trio to return to competition when he tees it up in two weeks at the Hero World Challenge, is in “full practice mode,” according to Golf Channel’s Tim Rosaforte.

Woods, who’s been off the PGA Tour since he missed the cut at the PGA Championship in August, is “hitting drivers down at Medalist Golf Club … and, by all accounts, looking extremely lean, much leaner than when we last saw him,” according to Rosaforte.

Tiger insider and Rosaforte colleague, Notah Begay, continues to insist he has not been hired on as his former Stanford teammate’s swing coach but has been serving in an advisory capacity, “as a sounding board” for his good friend.

“He is trying to remind Tiger of what he did well back in the ‘90s,” said Rosaforte, referring to the heyday of the 38-year-old 14-time major champion.

Rosaforte also suggested that Woods’ “new body type” was an effort to recreate the look and feel of his glory days. “Maybe it’s sort of a throwback to the ‘90s,” said Rosaforte.

Another aging superstar seeking a return to major-winning form that eluded him in 2014 is Mickelson, who believes that a new workout regime designed to slim his physique and boost his club-head speed will help him achieve a “great” 2015.

Lefty, taking a page out of the Rory McIlroy-Tiger playbook (don’t tell Brandel Chamblee), told Rosaforte that working out four mornings a week had gotten him halfway to his goal of losing 20 pounds and gaining 10 m.p.h. on his swing speed.

“He looks more athletic. He’s standing taller, carrying himself better,” performance coach Sean Cochran told Rosaforte about the results of his 5:45 a.m. sessions with Mickelson. “If I was a betting man, I’ll say he’ll come out hot in 2015.”

Mickelson, who’s been known to place a wager or two, would likely take that bet.

“Next year is going to be a great one,” Mickelson, who had only one top-10 finish in 2014, his worst season as a professional, said in a text message to Rosaforte.

The ever-optimistic five-time major champion made a similar prediction when he re-upped with Callaway last month.

“Backed by innovative technologies, industry-leading products, and the outstanding R&D group that works so closely with me,” Mickelson said in a Callaway press release after signing a multi-year extension with the company that’s supplied his gear for 10 years, “I honestly believe that these next few years will be the best of my career.”

Stay tuned; the popular PGA Tour superstar is expected to return to competition early next year, perhaps at the Humana Challenge at the end of January, according to Rosaforte.

As for Johnson, the big-hitter who said he left the tour in late July to address “personal challenges” may make his comeback at the Farmers Insurance Open on February 8. That’s a date that would allow him to be present when fiancee Paulina Gretzky delivers their first child, and, as Rosaforte noted Monday in Golf Digest, would mark the end of a reported six-month suspension for failing a drug test.

You don’t have to be a 40-something like Mickelson (44) or nearing the big 4-0 like Woods (39 on December 30) to require discipline to whip yourself into shape, and DJ (30) has apparently gone all out in his workout regimen. Inactive on the tour since the Canadian Open in late July, Johnson began hitting the gym hard last month.

Rosaforte reported that Johnson’s regimen of 30-mile bicycle rides and 40 sessions with trainer Joey Diovisalvi included two-a-days on the weights.

“I’ve never seen the guy more dialed in,” Diovisalvi said to Rosaforte, who also noted that coach Claude Harmon III was pleased with the efforts his student was making on the practice range.

The DJ of yore, who reportedly would appear for practices late or just blow them off, has been replaced by a diligent, conscientious worker.

Johnson’s sessions are “much more focused, he’s showing up on time, he’s not canceling out,” Rosaforte quoted Harmon as saying. “He is definitely engaged, and [Harmon] describes him as very healthy, happy, and lighthearted.”

He’d be a welcome addition to the Tour if he makes it back for one the marquee events on the early-season schedule.