DUESSELDORF, Germany (AP)—Mardy Fish and John Isner of the United States lost their matches to Argentina in the semifinals of the World Team Cup.

Juan Monaco edged Fish 7-6 (4), 7-5 Thursday, while Juan Ignacio Chela defeated John Isner 6-1, 7-6 (1).

Fish held opportunities in each set, but Monaco was able to hold off the challenge. Isner never looked comfortable against Chela in the opening set before taking it to a tiebreaker in the second set.

The other finalist will be decided Friday among Germany, Serbia, Russia and Spain.