The US Open champion said that he is struggling with a few areas of his game, but is hoping to find his top form during the tournament.
"I felt okay. I served pretty well, but I struggled a bit on the return especially at the beginning of the match," he told Sky Sports News.
"I've been playing very well in practice and felt confident today, but when the match started it's different conditions.
"I struggled with my timing. I've never played my best tennis at this tournament, but I'd like to change that. You'd hope after three or four matches you are starting to play better."
Murray will now play Jerzy Janowicz in the third round of the competition.