Defending champion Andy Murray reached the quarter-finals of the Madrid Open with an impressive 6-4 6-2 win over 16th seed Gilles Simon of France.
Second seed Murray, 28, broke Simon for the first time to take the opening set as part of a five-game winning run.
He then broke three times in the second set to complete victory in one hour, 38 minutes.
Britain's Murray will play Czech Tomas Berdych, a 7-6 7-5 winner over Spaniard David Ferrer, in the last eight.
Murray's serve was never broken and the power and variety of his ground strokes was too much for Simon, 31.
"It's always difficult to get the balance right against him because the better you hit the ball, the faster it comes back against him," Murray said.
"He uses the pace very well so I knew I needed to be patient and use variety, but also when the chance is there, go for it. Sometimes he makes players rush, but today I didn't have that problem. It was good from start to finish."
World number one Novak Djokovic, who won in Madrid in 2011, beat Spain's Roberto Bautista Agut 6-2 6-1 later on Thursday.
Four-time winner Rafael Nadal, who lost to Murray is last year's final, beat Sam Querrey of the United States 6-4 6-2 in the evening session.
Meanwhile Jamie Murray's five week run as the world's number one doubles player will come to an end on Monday.
He and Bruno Soares were beaten 6-4 7-6 (7-4) by Henri Kontinen and Murray's former partner John Peers in the second round.
Either Marcelo Melo, Nicolas Mahut or Horia Tecau will take over the top spot.
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