Rory McIlroy extended his winless streak in the majors to 15 last night despite finishing with a flourish in the US PGA at Bethpage Black.

The Holywood star (30) closed with a second successive one-under 69 to end the week tied for eighth with the likes of Shane Lowry on one-over par, too far behind to join the challengers trying wrest the Wanamaker Trophy from Brooks Koepka but close enough to believe that a fifth major win might not be too far away.

“I just need to play the first 27 holes better,” joked McIlroy, who was seven-over par and tied 123rd midway through his second round before clawing his way up the leaderboard to be provisionally tied 13th when he finished.

“I played the last 45 in six-under par, which was good on a tough course on a tough weekend. It’s really tough out there today but I tried to the very end.

“I could have let my head go down in the middle of that second round and be home in Florida right now but I wanted to be here for the weekend and I’m glad I could make the most of the opportunity I had to play and extra couple of days.”

If he fails to win the US Open at Pebble Beach or The Open at Royal Portrush, the world number four will have gone five years without adding to his tally of four major victories.

It's no great drought in the greater scheme of things when compared to the careers of great players such as Lee Trevino, who won five majors in six years but had to wait another 12 for number six, or Ben Crenshaw, who went 11 years between Masters wins.

Total dedication to the game is the biggest challenge facing a player who wins multiple majors quickly, McIlroy said when asked about Koepka’s biggest challenge.

“The biggest thing for me was finding the time to keep your game at the level it needs to be at,” said McIlroy, who was tied 17th for strokes gained putting for the week but ranked first on Sunday. “Saying no to things. Making sure that golf and your performance is still the No 1 priority when you start to win majors and get all these opportunities. 

“You have to make the most of those as well because we are here to make a living and have a livelihood and  enjoy ourselves but at the same time you have to keep your game at the level where it has to stay.”

However, it's no real surprise to some of McIlroy's fellow major winners, not that he's failed to add to his tally, but that the game's biggest events have become tougher to win than ever for a player whose power advantage has waned compared to the new kids on the block.

Pádraig Harrington pointed out more than five years ago that if the McIlroy was to achieve double-digits major victories, he would to have to start winning them in bunches before his advantage was eroded.

"If he putts okay, he's going to be right there,” Harrington said. "But with the kids coming out of college now, in five to 10 years’ time there are going to be a lot of players like that.

"So if Rory is to get to high numbers, it is the next number of years that will determine it. Rory's advantage will be eaten up in time too. 

"He is young and he's got time to win more majors, but the more he wins, the quicker the better. There might be three players like him now [2013] but in 10 years' time, there might be 15.”

McIlroy was not found wanting for power on Long Island where he made an eagle and 11 birdies but, he also had nine bogeys and two double bogeys.

His putting was respectable — he was 115th in round one, 16th in round two and 59th in round three before finally finding his range in round four. But it was not clinical enough to keep pace with the leaders and while not all majors require great power — next month's US Open will represent a return to the traditional test of accuracy and iron play associated with that event — the examination at Bethpage Black was such that it left many begging for mercy,

England's Paul Casey, who finished tied 38th on five-over after a closing 69, could only laugh as he walked off the course and spotted an emotional support dog.

"There's a dog near the scoring area with a little jacket on it that says emotional support dog, which is what I feel like I need after playing that golf course," Casey said with a grin.

Graeme McDowell, who was ranked 74th of the 82 players who made the cut with an average drive of 284 yards compared to Dustin Johnson's 329, is understanding of the challenge faced by McIlroy in an era when bigger, stronger and more athletic players are emerging with monotonous frequency.

"Rory is one of the best young players I have ever seen," McDowell said after carding a level par 70 to finish alongside Casey on five-over. "And he's still is one of the best I've ever seen. But it's hard to win and the pool of players that's winning on a week to week basis is impressive. 

"It feels like there are more of these guys that are so talented — a pool of 80 to 100 guys who can win any given week. As the golf ball goes further and these guys get stronger, how many more Cameron Champs are waiting in the wings? It feels like lots. 

"To me the ball speeds on the Web.com Tour and Challenge are faster than the PGA Tour. But thankfully there are not too many Bethpage Blacks on the schedule or I would have to think of getting another job."

McDowell knows that he will have a better chance of competing in this week's Charles Schwab Challenge at Colonial or on his return to Pebble Beach next month while his presence in The Open at Royal Portrush remains undecided.

"I'd have loved to have broken par out there," said the Portrush man, who was three-under par after five holes before making four bogeys and one birdie over the last 10 holes. "It was a battling level par and fairly happy to get off the golf course, I've got to be honest with you.

"My game feels good, it really does. I'm trying not to get too destroyed by this golf course. Obviously going out there, 17 behind a guy who is making it look awfully easy; this is not a golf course that I would pick for me in a major championship and Pebble Beach is a golf course that I would pick for me.

"I've got Colonial next week which is going to feel like a pitch-and-putt by comparison. I'm feeling a bit bruised and battered but I have to say, the game okay and looking forward to the next few weeks."

If he is to be at Royal Portrush, he has several routes into the field, as outined below:

OPEN CHAMPIONSHIP (OPEN) @ Royal Portrush Golf Club – July 18-21
• Winner of the PGA Championship (May 19).
• Top 50 from Official World Golf Ranking (May 27).
• Top 4, not otherwise exempt, inside top 12 at The Mizuno Open (June 2).
• Top 2, not otherwise exempt, from Order of Merit on Japan Golf Tour ending with Japan Golf Tour Championship (June 9).
• Top 3, not otherwise exempt, inside top 10 at the RBC Canadian Open (June 9).
• Winner of U.S. Open (June 16).
• Winner of British Amateur, if still an amateur (June 22).
• Top 2, not otherwise exempt, inside top 8 at the KOLON Korea Open (June 23).
• Top 5 and ties, not otherwise exempt, inside Top 20 in Race to Dubai thru the BMW International Open (June 23).
• Top 5 and ties, not otherwise exempt, inside Top 20 in FedExCup points thru the Travelers Championship (June 23).
• Winner of the International European Amateur Championship, if still an amateur (June 29).
• Top 3, not otherwise exempt, inside top 10 at the Andalucia Valderrama Masters (June 30).
• Top 2, not otherwise exempt, inside top 8 at the Rocket Mortgage Classic (June 30).
• Local Final Qualifying. Top 3 at each of four sites: Fairmont St. Andrews, Notts, Prince's, St. Annes Old Links (July 2).
• Top 3, not otherwise exempt, inside top 10 at the Dubai Duty Free Irish Open (July 7).
• Top 3, not otherwise exempt, inside top 10 at the Aberdeen Standard Investments Scottish Open (July 14).
• Top finisher, not otherwise exempt, inside top five at the John Deere Classic (July 14).