Andy Murray admits there is plenty of room for improvement after suffering a shock defeat to Teymuraz Gabashvili in the second round of the Citi Open in Washington.
The British No.1 and tournament top seed was making his first appearance on the US hard courts this year but went down 6-4 4-6 7-6(4) to the Russian, who is ranked 53rd in the world.
Murray was philosophical in defeat though and refused to panic, insisting he has plenty of time to improve certain areas of his game ahead of the final Grand Slam of the year in New York.
"I normally back myself to return a little bit better than I did. I think in the tie-break I don't think I put one return in the court when he was serving. I feel like I didn't do a good enough job of putting enough first serve points in the court," said Murray.
"It's obviously a disappointing match to lose but it wasn't like I was blown off the court in a match that I had no chance of winning. I feel like I put myself in a position to win the match. It was the first hard-court match for four-and-a-half months with only four or five days of preparation so I was happy with how I moved and did certain things on court.
"But there are some things for me to improve and hopefully with a few more days and having that match under my belt I'll be able to make some improvements for the next few weeks."
The world No.3 now moves on to Masters events at Montreal and Cincinnati before beginning his quest for a second US Open at Flushing Meadows on August 31.
Gabashvili, meanwhile, highlighted a rise in confidence as one of the key reasons for his success over the Scot. The 30-year-old overcame Benjamin Becker in the first round and will now face Ricardas Berankis in the last 16.
"I knew if I just played confident and try my weapons and let's see how it goes and it went to my side. The past three years I've become more confident in my play. Last year it was the best year in my career and this helped me to improve more this year," he said.
Gabashvili, nicknamed 'Tsunami', hit 11 aces on his way to victory.