Towering Croat Ivo Karlovic shattered the record for aces in a tour-level match with 78, but astoundingly lost to Radek Stepanek 7-6 (5), 6-7 (5), 6-7 (6), 7-6 (2), 16-14 yesterday in the first singles match of the Davis Cup semifinal between Croatia and the Czech Republic. The marathon contest, played before a raucous home-town crowd on an indoor red-clay court in Porec, Croatia, lasted five hours and 59 minutes. The 6-foot-10 Karlovic broke his own record of 55, established in a five-set loss to Lleyton Hewitt in the first round of the French Open in May. The defeat was particularly galling for Karlovic because he had four match points against Stepanek: three with the Czech serving at 4-5 and another at 11-12 in the final set of the match. After exchanging service breaks in the second and third games of the first set, Karlovic and Stepanek combined to hold serve 78 consecutive games. “We were not able to break each other,” Stepanek said. “The match was going crazy.” The end finally came in the 29th game of the fifth set, when Karlovic botched a high forehand volley near the net, slapping it long over the baseline to lose his serve. Stepanek held to close out the victory, but not before squandering a pair of match points. “It was a kind of lottery in the fifth set but I stayed mentally strong and it paid off in the end,” Stepanek said. Thomas Berdych put the Czech Republic up 2-0 with a 6-3, 6-3, 3-6, 4-6, 6-3 win over Marin Cilic in the second rubber.