MONACO (AP) France captain Guy Forget has chosen Gilles Simon to play singles against the United States in their Davis Cup quarterfinal Friday on clay.

Even though the 13th-ranked Simon is nursing a sore back and practiced little, Forget selected him Thursday ahead of lower-ranked Julien Benneteau and Michael Llodra.

Sixth-ranked Jo-Wilfried Tsonga will open against 19-year-old American Ryan Harrison at the Monte Carlo Country Club. Simon, who replaced the injured Gael Monfils, will play No. 11 John Isner.

American captain Jim Courier is without Mardy Fish, who pulled out with fatigue this week.

We're very prepared. We have a great team, a great coach and captain,'' said Harrison, whose only Davis Cup appearance came in the meaningless reverse singles during the 5-0 sweep of Switzerland in February.I think we're as prepared as can be.''

Brothers Bob and Mike Bryan will play Benneteau and Llodra in the doubles on Saturday. In reverse singles on Sunday, Isner opens against Tsonga and Harrison faces Simon.

Isner recently beat Simon at Indian Wells, but feels that win will count for little.

I don't think it's going to make that much of a difference,'' Isner said.It's Davis Cup. It's a whole different animal than a regular tournament. (Simon's) going to take to the court very confident.''