British number one Andy Murray overcame fitness concerns and an in-form Mikhail Kukushkin to win his opening match of 2012 at the Brisbane International.
Murray, who will be joined by his new coach Ivan Lendl in Queensland later this week, battled through 5-7 6-3 6-2.
The Scot, 24, appeared to be struggling with a lower back problem at times and also called for the trainer to remove strapping from his knee.
He will face world number 54 Gilles Muller of Luxembourg in round two.
Kazakhstan's Kukushkin, ranked 91 in the world, broke the Murray serve three times and held several set points in the opener but could not convert until the 12th game.
Murray was under more pressure early in the second but saved two more break points before breaking in game four and serving it out.
After a tight start to the final set, the world number four and top seed made the decisive break to lead 3-2 and sealed a hard-fought win after two hours and 10 minutes.
"He was hitting winners from all over the place," said Murray, who withdrew from the season-ending Tour Finals in London with an injured groin in his last singles match in November.
"I was a little bit slow but I wasn't expecting him to come out swinging like that.
"He was hitting the ball great so I was glad I was able to turn it around. You're meant to be ready from the start and I wasn't quite there today, but I played better towards the end, I started to move a little bit better.
"My body loosened up a little bit so hopefully I will pull up OK tomorrow."
In the women's event, fifth seed Kim Clijsters won her second-round match against Ana Ivanovic 6-1 1-6 6-3 in the final night match.