Andy Murray has admitted he will have to raise his game ahead of his second round Wimbledon encounter against Robin Haase on Thursday.
The Scot managed to see off the challenge of the Kazakh Mikhail Kukushkin in his opening round of the Grand Slam event, but it was no walk in the park for the British number one.
After claiming the first set 6-4, Murray’s first serve fell apart in the second which allowed his 27-year-old opponent to edge back into the contest.
The two-time Grand Slam champion, who is 3.50 to win Wimbledon again this year, did show his class to come out on top in the tie-break before seeing off Kukushkin in the third set.
With a tougher test against Haase to come, Murray knows he will have to make improvements going forward.
He told BBC Sport: “It was a tough match. I made it hard for myself at the end of the second set. He then started playing some very aggressive tennis. He was hitting it so low it was difficult to do anything.
“I am glad I got through, it was a hot day and he was a tough opponent. Towards the end of the second set I missed 10 or 11 first serves in a row and I gave him an opportunity.
“I was not surprised, I have seen some of his results when he has played on the big courts.
“There is definitely work to be done for but my opponent played very well and made it very difficult for me to play offensive. He made it very uncomfortable for me.”