Washington - Rory McIlroy has tweaked his swing after a lacklustre Masters, hoping a return to beloved Quail Hollow this week will set him up for major success at the PGA Championship.

The Northern Ireland star is among the favourites when the Wells Fargo Championship tees off on Thursday on a Charlotte, North Carolina, course where he has won twice in course-record fashion, a final-round 62 in 2010 bringing his first US PGA triumph and a 61 in 2015's third round setting up a seven-shot win.

"It's always a place that I look forward to coming to every year," McIlroy said on Wednesday.

"The course is in great shape. I'm excited to be playing again after a couple weeks off. Got a busy stretch coming up and hopefully I'll start off with a good tournament this week."

McIlroy, who turns 30 on Saturday, shared 21st at the Masters last month at Augusta National, missing another chance at the career Grand Slam a green jacket would provide as Tiger Woods produced his first major win since 2008.

Using video of his Masters swing during a two-week layoff, McIlroy worked on his game with coach Michael Bannon and has made minor fixes he hopes produce major results in two weeks when the PGA Championship, an event he has won twice, is staged at Bethpage Black.

"One of the good things about having two weeks off is you have time to delve into a couple of things," McIlroy said. "Just sort of delved into that a little bit and worked on a couple mechanics and feel a bit better about it."

Four-time major winner McIlroy worked on curving the ball less and getting his body rotation in better sync.

His solid but unspectacular Masters ended a run of seven US PGA events this year where McIlroy had placed in the top 10, including a victory at the Players Championship and a runner-up effort at the WGC Mexico Championship.

McIlroy is as concerned about his mental game as his physical one.

"If I look back through all the success I've had winning tournaments, whether it be a major or not, I always go back to the fact that I was in a really good place that week," McIlroy said.

"What will help me ultimately win more majors is being in the right place mentally."