Stepanek gave the Czech Republic its second straight Davis Cup title Sunday, sweeping past Dusan Lajovic in straight sets in the fifth and decisive match to secure a 3-2 win over Serbia in the final.
That made Stepanek the first player in the history of the tournament to decide two consecutive finals in the fifth match, having done the same against Spain's Nicolas Almagro last year.
"This is an amazing moment," said Stepanek, who beat the 117th-ranked Lajovic 6-3, 6-1, 6-1 after Novak Djokovic had levelled the series for Serbia at 2-2 earlier Sunday.
The Czech veteran converted his first match point with a smash to send about a thousand visiting Czech fans at Belgrade Arena into wild celebrations as they blew trumpets and beat their drums.
Stepanek spread his hands on the court as Tomas Berdych and other Czech teammates jumped on him.
"It's difficult to find right words for emotions I am going through now," Stepanek said. "It was a completely different experience than last year. I was very focused, concentrated, I knew what to do on court. We made history for our country today."
Last year's victory for the first for the Czechs as an independent nation. Serbia won its only crown in 2010, beating France in Belgrade.
Lajovic, who has a 5-12 record on the ATP tour and had never played in the Davis Cup before this weekend, replaced Janko Tipsarevic, who missed the final with a heel injury.
He also lost his first singles against Berdych on Friday — his first career best-of-five-sets match — and found himself thrust into by far the biggest match of his life against Stepanek. The 23-year-old Serb started well, however, breaking Stepanek in the opening game of the match. But the 34-year-old Czech responded swiftly with two consecutive breaks to take a 5-2 lead.
Stepanek controlled the match from then on, and broke Lajovic for 3-1 in the final set, and then added another before serving out the match.
"I was fighting to my last breath, but obviously this wasn't enough," Lajovic said. "Of course, I am very disappointed. Right now I need to cool off my head and think what to do next."
Serbia captain Bogdan Obradovic said his team's chances of winning the title were crippled by Tipsarevic's injury and a 12-month doping ban against Viktor Troicki, who helped Serbia win its only title.
"We couldn't find the real replacement for the two, it was like playing tennis without one leg," Bogdanovic said. "Dusan is the young gun in our team. Hopefully he is going to use the energy from the team and some experiences from those two matches for his career, even if it wasn't a success."
The Czechs got the crucial point in Saturday's doubles to go up 2-1. The second-ranked Djokovic then kept alive Serbia's hopes by beating Berdych 6-4, 7-6 (5), 6-2 earlier Sunday to improve his career record against the Czech to 15-2.
"We both entered this match with a lot of tension," Djokovic said. "I managed to break his resistance in the second set."
Berdych was leading 5-4 in the second-set tiebreaker when he sent wide an easy backhand volley at the net. Then he lost a point on his serve, and Djokovic took his first chance to serve out the set.
Djokovic, who improved his winning streak to 24 matches since losing the U.S. Open final against Rafael Nadal in September, converted his first match point with an ace, bringing cheers from the 17,000-strong boisterous Serbian crowd at the arena.
"It's really hard to find right and correct words to explain at what level he's playing and how strong Novak is," Berdych said. "He is now the best player when he's playing indoors, and that's what he proved today."
Associated Press writer Jovana Gec contributed to this report.