World number one and defending champion Novak Djokovic survived a second-set fightback by fellow Serbian Janko Tipsarevic to reach the semi-finals of the Dubai Tennis Championships.
Djokovic broke his opponent's serve twice to take the first set but Tipsarevic blasted back in the second and held set-point to take the match into a decider before the favourite prevailed 6-1 7-6 (8/6).
It was an important win for Djokovic, who was beaten by Tipsarevic in the World Tour Finals in London last December, and ensured his unbeaten start to the new season remained intact.
"I thought I started really well," Djokovic told atptour.com. "Then in the second set whenever I had break point he served well. We both got a bit nervous towards the end, and it was just luck to prevail."
Djokovic will face third seed Andy Murray in the semi-finals after the Scot overcame Czech Republic's Tomas Berdych for the first time in four meetings, winning 6-3 7-5 in one hour and 51 minutes.
Murray got off to a flying start by breaking Berdych in the second game of the match, but struggled in the second set, twice surrendering a break advantage before breaking for a third time to secure the victory.
The world number four conceded he had lost his way a little in the second set but was happy that he managed to get across the winning line.
"Tactically I was doing the right things, and then maybe got away from that a little bit," the 24-year-old said. "But I just hung in at the end. I fought and scrambled and did what I had to do to win."
Speaking before his clash with Djokovic was confirmed, Murray - reflecting on an epic encounter between the pair in the semi-finals of the Australian Open in January - said: "I would like to get a chance to play him again.
"Before the Indian Wells/Miami stretch it would be good to see exactly what I need to work on, where my game is.
"I had a great match with him in Australia, and hopefully I can reverse the result tomorrow."
Roger Federer breezed through to the last four, needing just 69 minutes to defeat Russian Mikhail Youzhny - whom he beat in the 2007 Dubai tournament final - 6-3 6-4.
Federer's last-four opponent will be in-form Juan Martin Del Potro, who followed up last week's tournament win in Marseille by easing past fourth-seeded Frenchman Jo-Wilfried Tsonga 7-6 (7/1) 6-2.
Del Potro kept his cool in the first set tie-break to nudge into the lead, then took advantage of both his break-point chances in the second set as he wrapped up his second victory in two weeks over Tsonga.