Harrison, Isner complete US rout of Switzerland (AP)

FRIBOURG, Switzerland ? The United States completed a 5-0 rout of Switzerland in the Davis Cup on Sunday, with 19-year-old Ryan Harrison and John Isner winning closing singles matches.

The U.S. was already assured of advancing after winning Saturday's doubles in the first-round series in the World Group. The Americans will play on the road in the April 6-8 quarterfinals against France or Canada.

Harrison made a winning Davis Cup debut, beating Michael Lammer 7-6 (0), 7-6 (4) to extend the Americans' lead to 4-0. Isner, who beat Roger Federer on Friday, ensured a shutout in defeating Marco Chuidinelli 6-3, 6-4.

Harrison was selected by captain Jim Courier after the U.S. sealed its victory Saturday when Mardy Fish and Mike Bryan beat Olympic doubles champions Federer and Stanislas Wawrinka.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

FRIBOURG, Switzerland (AP) ? Teenager Ryan Harrison made a winning Davis Cup debut for the United States on Sunday, beating Switzerland's Michael Lammer 7-6 (0), 7-6 (4) to extend the Americans' lead to 4-0 in their first-round series.

Harrison stepped up his play in the tiebreakers after showing an impressive all-around game to win in 2 hours, 14 minutes.

The 19-year-old right-hander was selected by captain Jim Courier after the U.S. sealed its victory Saturday, when Mardy Fish and Mike Bryan beat Olympic doubles champions Roger Federer and Stanislas Wawrinka.

Federer and Fish had been scheduled to play in Sunday's first singles match. The best-of-five series finishes with John Isner of the U.S. playing Marco Chuidinelli of Switzerland.

Source: http://us.rd.yahoo.com/dailynews/rss/sports/*http%3A//news.yahoo.com/s/ap/20120212/ap_on_sp_te_ga_su/ten_davis_cup_us_switzerland

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