Six years after sitting disconsolately in his hotel room in Akron wondering if he had the game to play with the big boys, Shane Lowry stands on top of the world safe in the knowledge that he’s now a man to be feared.

In fact, the new world No 19 began life as a World Golf Championship winner Sunday by setting his sights on Rory McIlroy’s Race to Dubai crown and his first major title in this week’s US PGA.

There was no wild party for a larger than life character who has transformed himself over the last two years into a player capable of just about anything in the game, just a few beers with the likes of Padraig Harrington and the caddies.

And he’s clearly bursting with confidence after proving to himself he really can produce the goods under pressure and hold off the game’s greatest players down the stretch.

Itching already to get back at it after having just “a couple of drinks” in celebration on Sunday night, Lowry is targeting a big week on the shores of Lake Michigan that would help him close the €770,661 gap on McIlroy in the Race to Dubai.

“I was walking down the 14th yesterday looking at leaderboards and saw names like Bubba Watson, Justin Rose and Jim Furyk chasing me down,” Lowry said yesterday as he pecked his way through hundreds of texts and tweets of congratulations.

“But I grabbed the bull by the horns and I won the tournament. And when you do something like that, you will always have that with you. 

“I now know that when I go into majors and big tournaments, I am going to be one of the players that people won’t want to see on the leaderboard.

“They will be saying, ‘Oh, Shane Lowry is chasing me down.’  So yes, I feel I can win the US PGA. I know going into this week that if I can put myself into a good position going into the back nine that it’s a case of ‘lets see what I can do from there’.”

Lowry didn’t go over the top with his celebrations on Sunday night, settling for a few beers with Harrington and a few of the caddies when he got to Whistling Straits

Admitting he’s now far more professional about everything he does, he said: “People have the wrong idea about me, but I don’t mind that at all. I am my own person. 

“The people around me know how hard I work and how much effort I have put into it and that’s all that matters. 

“People probably think I was out until all hours last night celebrating, but at the end of the day there is a big week this week. 

“Okay, I did have a few drinks — Padraig and Ronan Flood, Ken Comboy and Ricky Elliott and Pete Cowan were there. We had a couple of drinks in a bar in Sheboygan and were out of there at half 11. 

“The lads were happy for me and it was great to see them. But it is onwards and upwards now. That’s the way it is. 

“I feel like  I have matured as a person over the last umber of years, especially the last two years and I do treat myself and my body a lot better than I used to.  And I feel like I am getting the rewards now.”

Lowry is fourth in the Race to Dubai standings behind McIlroy, Danny Willett and Open runner up Louis Oosthuizen with €2,104,984.

And while he’s secured his PGA Tour card and could qualify for the FedEx Cup playoffs with a big week in the US PGA, a maiden major win would catapult him to superstar status.

He sees now reason why he can’t  win again his week on a course that will suit his game.

“It was a course I liked back in 2010— a good driver’s course —so the way I am hitting it, it will be good.”

While his FedEx Cup tally only begins this week as he wasn’t a full member until he won on Sunday, he’s not ruling that out either if he can have a big performance in Wisconsin. 

“I had a look at the Race to Dubai rankings and the world ranking when I got up today and to see yourself 19th in the world and fourth in the money list, it’s nice,” he said. “You say to yourself, that’s pretty cool. 

“And I know that I can win the Race to Dubai. To be honest, for the rest of the year, that’s probably my goal.”

McIlroy texted Lowry on Sunday night to congratulate him on his “pretty ballsy” victory and it was that ability to produce the shots and the putts under pressure that pleased him most.

Lowry said: “The par on 14 probably won me the tournament but the best moment was when I had that 10 footer on the last for birdie and I knew two putts would probably do it for me. 

“To hole that putt, to do that, says a lot about me. It shows I’ve got what it takes. I can do it when I need to.”

It’s been a rollercoaster three years for Lowry since he won his second tour title in Portugal in 2012.

He’s had a few close calls, finishing second to McIlroy in the BMW PGA at Wentworth last year and then coming up just short in the US Open in June before missing the cut in The Open at St Andrews.

He said: “I remember sitting in my hotel room in Akron on Friday evening on 16 over par in 2009, thinking to myself, am I good enough at all. 

“All of sudden six years later, I am standing on the 18th green with the trophy. It’s a bit weird. But it shows you how far I have come. 

“A lot of it is to do with the people I have surrounded myself with over the last few years. I put into play a good team of people. 

“I have Neil Manchip as coach since day one and Conor Ridge Horizon since day one  and Dermo on the bag basically since day one.

“And then I have brought in Robbie Cannon for fitness, and he’s been a big help this year and Shane Lawlor the physio, who is a big help the last couple of years. They are all good, positive people and there is a nice vibe. 

“Obviously my golf has improved and I have worked hard but I definitely owe those people a lot and I feel fortunate it has all come together nicely.

"I remember Conor putting his arm around me after The Open and saying, you just have to keep at it. Golf will pay you back when you least expect it. Thankfully it was last week.”