World No 4 Andy Murray overcame a gutsy display from Russian Igor Kunitsyn to win 6-2, 6-3 in a floodlit first-round encounter at the Dubai tennis championships.
After defending champion Novak Djokovic eased into Wednesday's second round with a straight-sets victory, the Briton started slowly in his first match since losing the Australian Open final to Roger Federer, surviving two break points in the opening game.
The Russian's high-energy approach disturbed a rusty Murray in an epic 24-minute second game which included 14 deuces.
Murray's right knee was wrapped in an ice pack before the game and the Scot visibly slumped after failing to convert an eighth break point, but won at the ninth attempt for a 2-0 lead.
"It was really tough - that was probably the longest game I've ever played on the tour," Murray said in a courtside interview.
"I served well. It's a pretty quick court compared to Australia and the balls are faster too."
A long Kunitsyn forehand gave the 22-year-old the opening set after 58 minutes.
Murray double-faulted to lose the opening game of the second set but a brutal forehand winner gave him an immediate break back.
However, he remained frustrated by his inability to exploit Kunitsyn's second serve, spinning his racket and talking under his breath.
A measured lob gave Kunitsyn break point at 2-2, with Murray hitting his racket on the ground in anger but the Scot delivered an 11th ace, eventually holding serve.
Kunitsyn saved two break points in the next game, but a third was beyond him and Murray edged 4-2 in front.
Murray will next play Italy's Andreas Seppi or Janko Tipsarevic of Serbia.
Novak Djokovic survived a late scare to defeat Spain's Guillermo Garcia-Lopez 6-4, 6-4. The crowd favourite was 5-0 ahead in the second set, before a determined Guillermo fought back to 5-4.
"It was all my fault," Djokovic told reporters. "I was playing well all the way up to 5-love and then just lost it. It's my first game outdoors since Australia, so (I'm) still getting used to the conditions."
The 2008 Australian champion raced into a 5-0 second-set lead, subduing his opponent with a torrent of powerful forehands, drop shots and astute net play.
Guillermo saved a match point as he broke Djokovic twice to reach 4-5. Roared on by a near-capacity crowd, Djokovic was stirred into action and although Guillermo saved a second match point, the Serb ended the contest with a sweet forehand down the line.
His win set up all an all-Serb second round clash with childhood friend Victor Troicki, who beat Rainer Schuettler 6-3 6-4.
Food poisoning could not stop Cypriot Marcos Baghdatis from defeating eighth seed Gilles Simon 7-6, 6-4.
"I was concentrating on not throwing up on court," the 24-year-old said. "I was suffering from food poisoning and had cramps in my stomach."
Spain's Feliciano Lopez, twice a finalist here, suffered a shock 7-6, 6-4 first-round defeat to Austrian qualifier Stefan Koubek.