MONTREAL: Andy Murray has seized the momentum a fortnight before the US Open, the Scot exploding into form with his fifth title of the season Sunday at the Montreal Masters.

Besides starting the week with a freshly minted world number two ranking, the only British man to ever lift a trophy in Canada will surely be wired for his title defence at the Cincinnati Masters. Murray celebrated his ascent to the second spot, sandwiched in between Roger Federer and Rafael Nadal, by fighting back in just under three hours to overhaul Juan Martin Del Potro 6-7 (4/7), 7-6 (7/3), 6-1 for the Canadian title.

His fifth title of the year pulled him level with Nadal for most in 2009.

While victories mean the world to him, there is no denying that Murray is pondering the important marker he passed by moving to his best-ever ranking.

"I love winning tournaments, every player will tell you the same," said the Scot. "But I've never been to number two before, that's all new to me.

"I've won a couple of Masters events and that still feels great. But maybe getting the new ranking means a little bit more right now."

Del Potro, winner a week ago in Washington, looked strong to start, but needed treatment on a shoulder problem in the second set and took an off-court injury time out to start the third before fading.

"I was so tired," he said. "I felt my chances in the second set tiebreak, but I didn't take them.

"I was trying until the last but it was so complicated for me," the South American added.

Murray lost a 62-minute opening set, but levelled by winning the tiebreaker in the second, then dominated in the third. "I had those three aces in the (second set) tiebreaker to get back into it," said Murray. "Juan Martin served unbelievably in the first two sets. I tried to stay in it to the end. It was tough conditions for both of us out here.

Murray said his next goal is winning Cincinnati again, where he will begin at mid-week after a first-round bye.

"I wanted to get matches this week, that was important," he said.

"The US Open is still a couple of weeks away, I'll focus on Cincy now and try to play well there. Each week is different." "I don't want to get too far ahead of myself," added Murray. "Becoming number two didn't distract me, I played well and put it to the back of my mind. I'll enjoy it over the next few days."