Murray is looking to defend the title he won in Doha last year
Britain's Andy Murray continued his defence of the Qatar Open title with an easy 6-2 6-4 win over Germany's Philipp Petzschner to reach the quarter-finals.
The world number four gave a near faultless display, dominating with some booming forehands, tireless defence and unplayable drop shots.
Murray will now face Ukrainian Sergiy Stakhovsky, who beat Alex Peya 7-5 6-3.
Rafael Nadal beat Slovak Karol Beck 6-1 6-2, while Roger Federer beat Italian Andreas Seppi 6-3 6-3.
It was Murray's first meeting with the 24-year-old Petzschner, ranked 66 in the world, and he won the first set in 37 minutes.
The Scot broke in game three of the second set to quickly wrap the game up.
After Murray beat Spain's Albert Montanes in the opening round on Tuesday, Petzschner was only able to show brief glimpses of his power game.
The opening two games went with serve but Murray looked in the mood for chasing everything down and his reward was an early break in an entertaining third game that had one rally lasting 23 shots.
The German looked a little short of ideas and after three aces Murray powered to a 3-1 lead and eventually won the set 6-2 with few problems.
In the second set, it was in the third game again that Petzschner's service crumbled as the Scot took it to love.
Serving at 5-3 down, Petzschner briefly sparked into life with some excellent serve and volleying, but Murray's strength proved too much.