In the second singles match, Andy Roddick of the United States outdueled Jan Kroslak of Slovakia, 6-4, 6-4, 6-7 (5-7), 7-6 (7-1).
Sampras, the all-time leader with 13 Grand Slam titles, improved his career Davis Cup record to 19-8. The 30-year-old had not played in the Davis Cup since 2000, when he won a reverse singles match to help the United States to a 3-2 victory over the Czech Republic.
Beck, 19, was required for Davis Cup duty after Karol Kucera and Dominik Hrbaty were sidelined with injuries.
After Sampras dropped the second set, U.S. captain Patrick McEnroe encouraged him to be more aggressive against his young opponent. The hard-serving Sampras then overwhelmed Beck in the third set.
Roddick, 19, increased his winning streak to start his Davis Cup career to four matches. He won both singles matches last year against India as the United States qualified for the World Group. Roddick beat Switzerland's George Bastl during the first round of the 2001 Davis Cup.
In other first-round Davis Cup action on Friday, France won its opening two singles matches against the Netherlands at Metz, France. Sebastien Grosjean defeated Edwin Kempes, 7-5, 7-6 (7-5), 6-2, and Arnaud Clement rallied to beat Sjeng Schalken, 7-5, 2-6, 6-7 (7-9), 6-4, 6-2.
The Czech Republic also took a 2-0 lead over Brazil. Jiri Novak overcame Andre Sa, 6-7 (10-12), 6-1, 6-1, 6-4, and Bohdan Ulihrach cruised to a 6-3, 6-4, 6-4 win over Fernando Meligeni.
Spain and Morocco split their singles matches Friday at Zaragoza. Juan Carlos Ferrero of Spain, routed Hicham Arazi of Morocco, 6-3, 6-1, 6-2. But Younes El Aynaoui of Morocco responded with a 6-3, 7-5, 6-4 victory over Alex Corretja of Spain.
Russia and Switzerland also finished Friday tied at one apiece. In a battle of young stars, Switzerland's Roger Federer dominated Russia's Marat Safin, 7-5, 6-1, 6-2. But Russian veteran Yevgeny Kafelnikov battled through the pressure and a one-set deficit to beat Swiss No. 2 Michel Kratochvil, 6-3, 4-6, 1-6, 7-6 (7-3), 6-2.
Missing Australian Open champion Thomas Johansson, Sweden still managed to split their first two singles encounters with Britain. Tim Henman of Britain defeated Jonas Bjorkman of Sweden, 6-4, 7-5, 4-6, 7-5. But Thomas Enqvist of Sweden edged Greg Rusedski of Britain, 7-6 (7-3), 7-6 (7-5), 6-2.
Playing without Tommy Haas, who is engaged in a dispute with his federation, Germany also split its opening two singles matches with Croatia at Zagreb. Rainer Schuettler of Germany battled past Ivan Ljubicic of Croatia, 5-7, 7-6 (7-3), 6-3, 7-6 (7-5). Then, reigning Wimbledon champion Goran Ivanisevic of Croatia overpowered Nicolas Kiefer of Germany, 7-6 (7-3), 6-3, 6-4.
Argentina took a 1-0 advantage over shorthanded Australia when Guillermo Canas rallied past Scott Draper, 6-4, 6-7 (4-7), 5-7, 6-4, 6-1. Gaston Gaudio of Argentina faces Andrew Ilie of Australia later Friday.
Australia is playing without world No. 1 Lleyton Hewitt, who is recovering from the chicken pox, and former U.S. Open champion Pat Rafter, who is taking time off from the game. Mark Philippoussis, who struggled with a knee injury in 2001, still is trying to regain full fitness.