British number one Andy Murray reached the Marseille Open semi-finals with a 7-5, 7-6 win over Frenchman Nicolas Mahut on Friday.
The first set was tight until Mahut dropped his serve in the last game with a double fault followed by a backhand error.
World number 11 Murray, seeded fourth in the indoor event, spurned two match points in the 10th game of the second set before going through 7-5 in the tiebreak after the unseeded Mahut hit a forehand wide.
"I thought it was an excellent match," said Murray, who started the year with a title in Doha but was then knocked out in the first round of the Australian Open before a knee injury forced him to withdraw from the Davis Cup tie with Argentina.
"I served a lot better than I did in my last two matches," added Murray, who downed 14 aces. "My serve is an area I've worked a lot on since coming back from Australia."
The Scot next faces another Frenchman, eighth-seeded Paul-Henri Mathieu, who reached the last four by beating compatriot and holder Gilles Simon 6-3 6-4.
Simon, who was impressive on Thursday knocking out Serbia's Novak Djokovic, the Australian Open champion and top seed here, was never in contention against Mathieu.
Simon said he was hampered by an abdominal injury sustained in the win over Djokovic, adding: "I couldn't serve properly".
Murray and Mathieu have met once, last year in Miami, with Murray winning in three sets after saving two match points.
Marcos Baghdatis of Cyprus, seeded sixth, upset third seed Mikhail Youzhny of Russia 7-6, 6-3 to set up a semi-final with Mario Ancic.
Croatia's Ancic, who has dropped out of the top 100 after a year away from the game because of mononucleosis, served 25 aces to knock out Swede Robin Soderling 6-3, 6-7, 6-2.