BELGRADE (AFP) Serbia secured their first appearance in the Davis Cup finals after defeating the Czech Republic 3-2 on Sunday in a tense semi-final which went down to the final singles rubber. Janko Tipsarevic led Serbia to victory with a straight sets victory over Czech Radek Stepanek in the decider after world number two Novak Djokovic had defeated Tomas Berdych 4-6, 6-3, 6-2, 6-4 before more than 15,000 fans in the Belgrade sports Arena. Tipsarevic, ranked 37th in the world, gave his best in the first set, boosted by Djokovics victory, securing it 6-0. But the second set saw him buckle a little under pressure, with Stepanek quickly seizing the opportunity to force a tie-break. However Tipsarevic dug deep to prevail 8-6. The third set started with Tipsarevics break, allowing Stepanek only several clean serves. He missed two match balls but then secured the set 6-4 to put Serbia into the finals. Earlier Djokovic defeated Berdych despite losing the first set 4-6. There was drama then when Djokovic stumbled and fell on his right knee. Serbias coach Bogdan Obradovic checked him out and after a tense scare, Djokovic returned to the court with a bandaged knee. That near ten-minute pause broke Berdychs rhythm and Djokovic managed to slowly turn the game.. I did not feel well at the start of the match, but the fall energised me, it woke me up, he said. Djokovic praised the Czech Republic, saying they were opponents to be respected. Disappointed Bardych said the Davis Cup matches are the toughest in tennis. The pressure is enormous, almost impossible to overcome, he said. On Saturday Djokovic had been unable to prevent his country from trailing 2-1 n Saturday. Czech pair Stepanek and Berdych beat Djokovic and Nenad Zimonjic by three sets to one. Djokovic, who was initially reported to have withdrawn due to stomach problems from Fridays match, later said in a statement he was actually still tired after hard efforts at the US Open and the long trip overseas. Serbias top player had only returned from America early on Wednesday after losing to Rafael Nadal in the rain-delayed US Open final on Monday. Serbia, who have never played in a Davis Cup final, reached this stage by defeating the United States 3-2 in Belgrade and then cruising past Croatia 4-1 in the quarter-finals in Split.