Ice-cool Grigor Dimitrov insisted he never doubted he would end Andy Murray’s reign as Wimbledon champion.

Dimitrov caused one of the shocks of the tournament as he dispatched third seed Murray with a 6-1 7-6 (7-4) 6-2 victory in the quarter-finals on Wednesday.

The 23-year-old Bulgarian’s remarkably composed performance rocked Centre Court and earned him a first grand slam semi-final, against top seed Novak Djokovic on Friday.

But Dimitrov, the boyfriend of Maria Sharapova, showed no signs of shock at a breakthrough triumph that should herald his arrival as one of the sport’s new stars.

Asked if he was surprised by the ease with which he defeated Murray, who had made the Wimbledon semi-finals five years in a row and was on a 17-match winning run at the All England Club, Dimitrov said: “No. Why would I have to be surprised? I’m proud of what I did. But it’s something that I’ve worked for, to get onto that stage, come out, and switch to another gear.”

Dimitrov has been a good friend of Murray’s but he risked irking the world No.5 by claiming he could tell his frequent practice partner was out of sorts from the way he was hitting in the pre-match warm-up.

He also added that Murray’s impressive wins earlier in the tournament meant nothing once he faced a higher quality opponent

“I know how he’s striking the ball when he’s at his best. I know how he’s playing when he’s not at his best,” Dimitrov said.

Transformed since hiring Australian coach Roger Rasheed, Dimitrov, who won the Wimbledon warm-up at Queen’s Club last month, is finally making good on the vast potential that has earned so many comparisons to Roger Federer.

Dimitrov’s victory also comes hot on the heels of Australian teenager Nick Kyrgios’s stunning win against world No.1 Rafael Nadal and the emergence of Canada’s Milos Raonic and Japan’s Kei Nishikori.

“What can I say? We want to win. I think the younger guys, we want to come on that stage. We strive for this,” Dimitrov said.