CINCINNATI, USA (AP) — Andy Murray's gold medal is back home on a cabinet. He hasn't even had time to pick an appropriate spot for the grandest prize of his career.

There's a more immediate challenge: get back in form for the US Open.

Murray took a few days off to let a sore left knee heal and get some needed rest for the start of the Western & Southern Open in suburban Cincinnati. The tournament opened yesterday with an evening match between James Blake and Kevin Anderson.

Murray is the defending champion in Cincinnati, but a worn-down one after the greatest moment of the Scot's tennis career.

He barely had time to celebrate his Olympics gold medal win over Roger Federer at Wimbledon, spending the next day doing interviews and having dinner with his friends. The following morning, he was on a plane for Toronto and the Rogers Cup.

After two days of matches, he withdrew last Thursday because of the sore knee and tiredness from the hectic few days. Murray blamed the soreness on having to adjust overnight from Wimbledon's soft grass to the hard courts.

"Going onto a new surface, that presents new challenges," Murray said yesterday. "I felt good after winning the gold medal, but coming over to play on hard courts, your body starts to hurt a little bit, you're sore in the joints.

"You have to work on different shots as well. So that can occupy your mind a bit. You're not feeling great straight away. Switching surfaces is a new challenge, something that's taken me a few days to adjust."

Murray will be one of the top draws in a tournament missing Rafael Nadal, who dropped out because of a sore knee, and defending champion Maria Sharapova, who is recovering from a stomach virus.

He's already had quite a summer.

Murray reached the final at Wimbledon for the first time, but lost to Federer, falling to 0-4 in Grand Slam final. He returned to the chewed-up grass at centre court a few days later, coming to terms with the disappointing loss.

"I was obviously pretty upset afterward for a couple of days after that," Murray said. "After going back — I don't know if I just kind of moved on after that or what, but it seemed to help. I got on the practice court a few days afterward. Before when I lost in Slam finals, I struggled for a few weeks, sometimes a few months afterward."

Beating Federer on the same court for the gold medal a few weeks later was the best moment of his career, giving him momentum as he gets ready for the US Open.

"Moving forward, you never know how much things are going to help you," he said. "I'm sure my confidence will increase. I think the Wimbledon final and the Wimbledon (Olympic) tournament gave me extra confidence because I went into the final a lot calmer. Just having that experience of playing under that much pressure probably helped me."

There wasn't much time to celebrate. He hasn't even had a chance to find an appropriate place for his golden keepsake.

"The medal's there on top of the cabinet, and I spoke to my girlfriend today and asked what she's done with it," Murray said. "She said she left it there. I'll try to get (it) in a better place when I get back."