Ivo Karlovic has earned a spot in the third round of the Rogers Cup after overcoming the challenge of home favourite Milos Raonic with a 7-6 7-6 victory.

In a battle between two of the best serves on the ATP Tour, it was the experienced Croatian who held his nerve at the key moments in the match as he sent the eighth seed crashing out of the tournament.

Raonic was forced to survive four break points in one game during the opening set, but with both players digging themselves out of trouble with huge first serves, a tie-break seemed inevitable.

Karlovic offered a sign of what was to come later in the contest as he quickly clinched the control in the tie-break before securing a 7-1 win as Raonic's errors gifted his opponent the lead.

The second set followed a similar pattern, but it looked like the Canadian had passed a key test when he survived three match points in the 10th game, with the crowd coming to life after two fine winners from the 24-year-old.

However, Karlovic refused to be denied in the tie-break that followed as he once again capitalised on errors to claim another 7-1 success and a spot in the third round.