Andy Murray has expressed his belief that he executed his gameplan effectively to see off Grigor Dimitrov in four sets in the last 16 of the Australian Open.

The sixth seed had to dig deep to avoid going five sets with the talented Bulgarian, but the three-time Melbourne runner-up was pleased with his performance in a match that didn't finish until past midnight in the Rod Laver Arena.

The 27-year-old told reporters: "I thought I played well. I thought Grigor started the match extremely well. He came out very aggressive, very explosive.

"But it's tough to keep that sort of level of intensity up. And then once I got myself into the match, I felt like I was able to dictate a lot of the points. I thought tactically I played a good match."

Murray will now play Australia's Nick Kyrgios, who overturned a two-set deficit to beat Andreas Seppi, in the quarter-finals.