Under Armour’s tagline for Jordan Spieth at this week’s PGA Championship is “GO GET TH4T.”

It’s clever. You see, “Go get that” was what he mouthed to caddie Michael Greller after dropping a 50-footer to retake the lead at the Open. A lead he didn’t relinquish. The four, meanwhile, represents the PGA Championship – the fourth and final leg of Spieth’s bid for a career Grand Slam.

It’s not a case of if, but when Spieth will win the PGA Championship and become just the sixth player to lift all four of golf’s biggest prizes.

Jack Nicklaus, Tiger Woods, Ben Hogan, Gary Player, Gene Sarazen, and then Spieth. Not bad company. (And let’s not forget both Rory McIlroy and Phil Mickelson have chances to claim the Grand Slam at the next two majors.)

If Spieth wraps his arms around that huge Wanamaker Trophy on Sunday, he will be also become the youngest to do it by several months. Spieth turned 24 just a few days after the sun had settled on Royal Birkdale, while Woods was five months short of his 25th birthday when won the first of his two Grand Slams.

“Do I have to be the youngest? No, I don’t feel that kind of pressure,” the world’s No. 2 player told reporters in the build up to Quail Hollow.

While we all get giddy about Spieth becoming the youngest player to win the Grand Slam – and why not? We love seeing players make history – the man himself is playing it cool.

“It’s not a burning desire to have to be the youngest to do something, and that would be the only reason there would be added expectations.

“I’m about as free and relaxed at a major than I think I’ve ever felt.

“It was only two weeks ago that I was able to get the third leg and that’s so fresh in my mind. I’m so happy about that that I can’t add pressure to this week. I’m free-rolling and it feels good.”

And why wouldn’t he feel relaxed? He’s barely in his mid-20s. If he doesn’t win the PGA Championship this year, he’ll have at least 20 more attempts at it.

Coming into this week, all the focus was on McIlroy and Rickie Fowler. Both have won at Quail Hollow – albeit a very different Quail Hollow – while McIlroy’s caddie antics in the past few weeks have put the spotlight firmly on man from Holywood.

If anything, this was the best chance Spieth of ever going for the Grand Slam while slipping under the radar. And if it wasn’t for late back-to-back birdies, we might be already writing off his chances of doing it this year.

Starting on the 10th alongside the year’s other major winners, Sergio Garcia and Brooks Koepka, Spieth had to wait until 15 to move into red figures after a tidy up-and-down from off the right side of the green at the par 5.

But when most expected him to start eating away at the tournament leaders, he promptly found two bunkers at 16 and gave his shot back immediately.

Spieth also had bunker problems at the newly-constructed 1st, before three-putts at both the 5th and 6th left Spieth 3-over with two to play. You don’t often see Jordan Spieth and three-putts talked about in the same sentence – especially when he had already done this earlier in the day…

But birdies at 8 and 9 – his 17th and 18th – thanks to what Spieth later described as a “phenomenal” hybrid shot and a “fantastic” wedge left him just five off the lead and still in with a shout of golf’s Holy Grail. (Well, the other one.)

“It’s much easier when you are on the front page of the leaderboard than it is coming from behind,” Spieth told reporters. He didn’t sound quite as relaxed as he had 24 hours before.

“Given it’s the first round I know I’m still in it, but I know that tomorrow’s round becomes that much more important to work my way and stay in it. I’ve got to make up ground.

“If I’m five back at the start of the day, I’ve got to be less than five back after Friday to really feel like I can play the way this golf course needs to be played and still be able to win.

He might say he’s relaxed about the Grand Slam attempt, but he will be eager to get the job done this week. As the years go by, it’ll only get harder and harder.

To get over the line this week, he needs to overtake both McIlroy and Fowler, as well as world No. 1 Dustin Johnson, Jason Day, Justin Rose, Adam Scott, Louis Oosthuizen, Hideki Matsuyama, Jon Rahm, and his sparring partner from the Open, Matt Kuchar.

One hand on the Grand Slam? It’s barely even a finger. But nothing surprises us about Spieth.

Now GO GET TH4T, Jordan.

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