Murray was playing Melzer for the first time
Andy Murray moved into the third round of the Pacific Life Open with a less than convincing win over Jurgen Melzer.
The British number one had a bye in the first round and after losing the first set he sealed a 3-6 6-3 6-3 win.
It was a lacklustre first set from the Scot as Melzer broke twice on his way to winning the opening four games.
But despite appearing to struggle with a back injury, Murray, 20, won the final two sets to book a meeting with Ivo Karlovic in the next round.
Murray's was a fractious affair at times with both the Scot and Melzer reacting angrily to various decisions from the officials.
But Murray held his nerve as Melzer, ranked 85 in the world, struggled to maintain his impressive early form.
The British number one's hopes of progress in the Californian desert received a boost when Andy Roddick - who Murray could have faced in the fourth round - was beaten by Tommy Haas.
"I played really well here and like the conditions," said Murray, the world number 11.
"My game feels really good - I am moving well and volleying well. If I can maintain the level I had for the second and third sets I have a good chance of doing well here."
However, Murray says he expects another tough test against big-serving Karlovic.
"It's one of those matches where I will have to play very solid and take my chances when I get them, there might not be many," said the 20-year-old, who beat Karlovic in San Jose last year.
"But when I played him before I broke him two or three times and managed to come through against him.
"In conditions like this with the balls flying like they do here it is going to be tough to break him."