Rory McIlroy might be a better player than he was in 2014 but his form in majors remains a massive question mark as he bids to end his near 10-year drought in the 106th PGA Championship at Valhalla this week.

The world number two has won 21 times worldwide since he captured his fourth Major title in the PGA Championship at Valhalla in 2014.

But despite ranking up 20 top-10 finishes in the 35 majors he’s played since that fourth major triumph, the Co Down man has consistently failed to produce the same killer instinct he showed here in Kentucky a decade ago.

Despite all his dominance and his remarkable consistency, the Holywood star has given himself just four realistic chances to win a major and failed to break 70 in any of those final rounds.

In the 2018 Masters, he was three shots adrift of Patrick Reed but shot 74 to tied for fifth.

Three years later he was tied for fourth heading into the final round of the US Open at Torrey Pines, a shot better than eventual winner Jon Rahm, and shot 73 to finish five behind.

At St Andrews in The Open in 2022 he went into the final round tied for the lead with Viktor Hovland and had 36 putts in a closing 70 to finish two shots behind Cameron Smith.

As for last year, he entered the final round of the US Open at LA Country Club just a shot behind Rickie Fowler and eventual winner Wyndham Clark and played the back nine in one over, taking 34 putts, to finish one behind.

They say there are lies, damned lies and statistics but McIlroy’s biggest challenge this week is proving these numbers are nothing more than a coincidence and not a sign that despite his brilliance in regular events, he lacks the killer instinct he showed over the first eight years of his major career.

In the 92 major rounds he played from 2007 to 2014, he led or co-led after 17 of them, winning four titles.

Since then he’s played no fewer than 126 major rounds and led or co-led after just two.

It’s a galling statistic that speaks not only to the pressure McIlroy is under to deliver on the promise he showed early in his career but the increased competition he faces at the top of the game.

Brooks Koepka has won five Majors in his last 25 starts and the defending champion is not even McIlroy’s biggest rival this week.

Even after a three-week break, world number one Scottie Scheffler remains the man to beat on a 7,609-yard brute of a golf course that will require long, straight driving and pinpoint iron play.

So what eats McIlroy?

For Paul McGinley, it’s a question of getting the right break at the right time, as he did here in 2014.

“There's no doubt there is a psychological build-up to getting over the line in these major championships that he hasn't circumnavigated yet,” McGinley said this week.

“And I say yet because I really do feel that if he gets one, maybe not the floodgates will open because there’s too much competition for that, but certainly, there's another three or four majors in Rory McIlroy.

‘To win a major not having won one for 10 years, that’s always going to be very difficult. But you would have to think that at a golf course like this, coming in inspired and in form, that's the kind of thing that could ignite him.

“But look, we've said that so many times in the last 10 years. He's primed to win and it hasn't happened. I think he needs a couple of things to happen for him at the right moment in time.

“I go back to 2014 when he was here and he hit a necky three-wood (at the 10th in the final round) when he was out of position and had lost the lead and he got a good kick that bounced up to six feet and he made eagle. Then the pointy elbows come out and off he goes.”

The fact remains that McIlroy admitted during the second season of Netflix’s second season of Full Swing, broadcast in March, that he doesn't feel like the same player who won four majors by the age of 25.

"I know that clock is ticking," the Holywood star said at the start of the series. "I was able to knock off four major championships pretty quickly in my career, but I've been stuck on four for a while.

"I don't deserve and no one deserves anything in this game. Like nothing is handed to you. It's all earned and I feel ready to earn it again."

Losing out in the PGA Championship at Oak Hill last year, where Koepka overtook him with five major wins, was a serious blow.

"It's a spiral," he said of what it feels like to try and win majors. "When you've momentum and things are going your way, the spiral works upwards. But if you get an unlucky break, you hit a shot you thought was going to be good and it didn't end up good, it just starts going the other way a little bit."

He described Oak Hill as a wake-up call and now is the moment to show he’s fully awake.

While he’s second favourite behind Scheffler, McIlroy is still considered a better bet by the bookies than Koepka, Xander Schauffele, Jon Rahm and Ludvig Aberg, which puts in context the scale of the challenge facing Shane Lowry and Pádraig Harrington.

If he putts well, Lowry has the long game and the skills around the green to challenge all comers. But as McIlroy knows, holing those key putts in the heat of major battle remains a massive challenge, even for the best players of the last ten years.

Harrington and Lowry differ when it comes to how to tackle the course.

“There's no doubt that with the length some people are going to suffer,” Harrington said. “It pays this week to be a real bomber of the ball. There's two ways to drive it well — hit a decently long and straight, or hit it mega-long. So we'll hopefully try and get into the decently long and straight.”

For Lowry, precision will trump power in the end.

“Although it will suit longer hitters, I don't think you can overpower this place,” he said. “The rough is going to become quite difficult so I feel like I can compete this week.”

That said, Lowry knows if he finishes ahead of McIlroy, he’ll likely contend.

“People will be shocked if he doesn't contend this week,” he said. "You know, as your career goes on, and it gets longer and longer, you have your ups and your downs, and everyone has them. You just have to kind of get on with it and keep chipping away and keep trying as hard as you can. And that's what I'm doing.”

For Scheffler, whose caddie will take Saturday off to attend his daughter’s high school graduation, he’s just hoping good golf will be rewarded.

“This is a place where I feel like when you're hitting it really well, the golf course can open up for you,” Scheffler said. “And there's definitely a lot of holes where you've got to put the ball in play, just with the thick rough.

“I think what we're looking for is to be rewarded for good shots and punished for bad ones, and from what I've seen around this golf course, it seems like an appropriate test.”