Nadal not satisfied in quick-fire Melbourne Park opener

Rafael Nadal's Australian Open rivals should be worried after the Spaniard said his game will improve the deeper he goes at 2018's first grand slam.

Nadal was in superb form to defeat Victor Estrella Burgos 6-1 6-1 6-1 in the opening round at Melbourne Park on Monday, showing no signs of the knee problems that have been troubling him.

The world number one was rarely tested by his Dominican opponent, but when Burgos was able to apply some pressure Nadal answered in emphatic style.

Nadal's forehand was working beautifully on Rod Laver Arena, the 31-year-old finding the lines with cross-court and down-the-line winners with ease.

And he expects to get even better as his fitness improves with time on court, a worrying thought for those competing for the grand slam title this month.

"Happy for the start, of course," he said. "It is a positive start with a good result.

"If I do months without playing [an] official match [it] is always a little bit more difficult. But I started with positive feelings. That's the most important thing for me now.

"Of course, there are things to improve, but the things that I need to improve, the matches will give me. Victories are the most important thing now."

Nadal will meet Leonardo Mayer in round two, the Argentine having beaten Nicolas Jarry in straight sets.