Rory McIlroy says "it's only a matter" of time before he becomes the world's top-ranked golfer again, after four years away from the summit.

The 30-year-old won €14 million ($15 million) last week by winning the Tour Championship at East Lake Golf Club in Atlanta, and this week he is competing at the Omega European Masters in Switzerland.

He finished up his first round at the Golf-Club Crans-sur-Sierre on three-under-par, hitting six birdies and three bogeys. Speaking after the 18 holes, McIlroy said to Sky Sports, "I played well on the back nine, which was our front nine. To play that nine in three-under I thought was good. I took advantage of a couple the shorter par fours on the front-nine but I made a couple of bogeys there as well.

"Overall it was okay, it's so different to the golf I've been playing the last few weeks, so just trying to adjust and get used to these greens again and how far the ball is going and what the ball is going to do out of the rough. But, I felt like I did okay.

"I think if I have to play a tournament this week, I wouldn't want to play anywhere else, that's the way I put it. It's beautiful, I'm here with my wife and her parents and we're having a great time - they went up to the Matterhorn yesterday. It's a beautiful place, and I'm glad I'm back after all these years. Hopefully, I can play a bit of good golf over the next three days and give myself a chance."

Following his victory in Atlanta last weekend, McIlroy is ranked number third in the world rankings. However, he wants to be the best again, "I feel like I am playing my best, I am the best player in the world.

"And I'd like to get back there. Its been a goal of mine for a while, I haven't experienced that summit for the last four years. I feel like with the work I'm putting in and the consistent golf I'm playing, It's only a matter of time."