Andy Murray has booked his place in the quarter-finals at Doha after easing past Germany's Philipp Petzschner, 6-2 6-4.
The first two games went with serve but Murray achieved an early break in the third game that had one rally lasting 23 shots. Murray took a 3-1 lead with three aces, and eventually won the first set in 37 minutes.
Murray, who was in complete control throughout the match, broke in the third game in the second set to comfortably seal his place in the quarter-finals.