Roger Federer is "happy" with his current form following his straight-sets win over Bernard Tomic at the Cincinnati Masters.

The Swiss admitted that it is difficult to assess his game in two-set matches, but claimed to be satisfied with his overall performance.

"Overall I'm happy, but it's hard to judge my game in these quick conditions," he said.

"I'm especially happy with my ball-striking, though my serve was a bit off. Overall it was a good performance, I'm playing as well as I want to right now."

Federer overcame the Australian 6-2 6-4 to reach the quarter-finals of the competition, where he will meet Mardy Fish.