Jan Hajek and Lukas Rosol both won their opening singles matches on Friday to give the defending champions Czech Republic a comfortable 2-0 lead over Kazakhstan in their Davis Cup quarter-final.
Hajek defeated Mikhail Kukushkin 6-3, 6-2, 6-4 before Rosol rallied to beat Andrey Golubev 4-6, 6-4, 6-2, 7-6 (6) in the second singles on clay at the National Tennis Centre.
"It's a fantastic result to lead 2-0 over Kazakhstan on the first day," Czech captain Jaroslav Navratil said.
Golubev opened strongly, breaking Rosol with a backhand winner in the fifth game, and looked the better player until the 10th game of the second set, losing only 14 points on his serve.
But Rosol levelled the match when Golubev netted a forehand, and the 63rd-ranked Czech then broke Golubev twice in the third set. Both players were broken once each in the fourth set, before Rosol converted his second match point in the tiebreaker with a forehand volley.
"Not all was as I expected at the beginning of the match but then I seized the initiative and won the match," Rosol said.
"I do not think about my match on Sunday - we can decide the tie tomorrow in the doubles."
The Czech Republic are without Tomas Berdych, who has a shoulder injury. Their No. 2 player Radek Stepanek, who had a neck operation in January, was rested for the opening singles but is set to play doubles on Saturday with Ivo Minar against Evgeny Korolev and Yuriy Schukin.
Golubev was up a break in the fourth set but missed his chance to level to the match.
"I had a set point at 5-4 in the fourth set but lost my serve," Golubev said.
"He played perfectly and gave no chances - he was returning every difficult shot. I tried to risk but made even more mistakes. It was not my day"
Kazakhstan's Mikhail Kukushkin
"I was back into the game and tried to make it my way but he (Rosol) served hard and gave me no chance."
Hajek saved a break point in the third game before breaking Kukushkin in the eighth and then serving out the first set. The Czech won five consecutive games in the second set and broke immediately in the third. Serving for the match, Hajek jumped to a 40-love lead and sealed the victory with backhand shot down the line on his first match point.
"Despite the scoreline, it was a tough match," Hajek said.
"We chose the right tactics for the match and it led us to success."
Kukushkin, who beat Hajek to score the winning point in Kazakhstan's 3-2 surprise victory over the Czechs in the first round in 2011, couldn't challenge his opponent's solid game this time.
"Nothing worked with me today," Kukushkin said.
"He played perfectly and gave no chances - he was returning every difficult shot. I tried to risk but made even more mistakes. It was not my day."
It was the first loss at home for Kukushkin, who has a 12-6 record in the competition.
The Czech Republic beat Spain in the final last year for their first title as an independent nation. Kazakhstan are looking for their first semi-final appearance.
The winner of the best-of-five series will face either Argentina or France in the semi-finals in September.