Rafael Nadal continued his pursuit of a record-breaking 21st major title by beating Karen Khachanov in four sets to reach the Australian Open fourth round.

Nadal, the 2009 champion and five-time finalist, defeated Russian 28th seed Khachanov 6-3 6-2 3-6 6-1 in Melbourne.

The Spanish sixth seed faces France's Adrian Mannarino in the last 16.

Mannarino came through a mammoth four-set match against Russia's 18th seed Aslan Karatsev that lasted four hours and 48 minutes.

[Source: BBC]