Andy Murray will advance to the semifinals of the 2011 U.S. Open after defeating John Isner in a tight four-set match, 7-5, 6-4, 3-6, 7-6. Murray played the type of technical, defensive tennis that he has become known for, forcing Isner into 54 unforced errors in contrast to 20 for himself.
After taking the first two sets, Murray appeared headed to a straight-set victory. Isner looked sluggish early, struggling to keep up with Murray's baseline returns. He seemed to gain a second wind in the third set, however, breaking Murray in the second game to go up 2-0 in the set. Isner would go on to win the set 6-3 while Murray showed his frustration by cursing into his sweat towel.
Both players traded serves in the fourth set to force a tiebreak. After nearly three and a half hours, Murray would win the tiebreak 7-2 to take the match. The winner between Andy Roddick and Rafael Nadal later in the day will face Murray in Saturday's semifinal.