Andy Murray has admitted that he was far from his best in his first outing as world number one at a Grand Slam, having been given a stern test by Illya Marchenko.

The five-time Australian Open finalist kicked off his first major of the year with a 7-5 7-6(5) 6-2 win over the Ukrainian in a match that lasted close to three hours.

Murray struggled at times and made three double-faults and a forehand error in the first game, but he was able to get over the line in a simple enough manner in the end to set up a meeting with Russia's Andrey Rublev in round two.

Speaking after the match, the Scotsman is quoted by BBC Sport as saying: "I don't think it was the best match. The conditions were pretty different to what we've been practising in. The last week's been pretty cool. When it's like that, the ball is bouncing a bit lower and it is a bit easier to control.

"I was a bit tentative because of that. And I didn't serve that well either. So you end up having to work really hard on a lot of your service games when it's like that."

Fellow Brit Dan Evans also made it through to round two relatively unscathed in Melbourne, but Aljaz Bedene fell to a four-sets defeat at the hands of Victor Estrella Burgos.