Grigor Dimitrov has advanced through to the Australian Open third round with a four-set triumph over Lukas Lacko.

The 10th seed dropped the second set but he hit 62 winners on his way to a 6-3 6-7 6-3 6-3 victory.

Both men came out firing during the opening exchanges but it was Dimitrov, who is looking to better his last-eight effort from 12 months ago, who broke twice to take the first set in 36 minutes.

However, Lacko, who was striking the ball as clean as his Bulgarian opponent, didn't back down and after taking the set to a tie-break, he levelled the match after getting the better of Dimitrov over a total of 22 points.

Dimitrov didn't panic though, and as he continued to rack up more winners, he saved three break points on the way to regaining his lead before gaining the early advantage at the beginning of the fourth.

Lacko struck back to suggest that he was capable of extending the match into a decider, but Dimitrov found an instant response before serving out the match.

Marcos Baghdatis lies in wait for Dimitrov in the next round, with that match taking place on Friday.