Novak Djokovic was unable to lead Serbia to a Davis Cup crown on Sunday, but a streak of 24 straight victories left him upbeat for next season in which he vows to focus on grand slam titles.

The world No.2 swept Radek Stepanek and Tomas Berdych in straight sets, but his two points did not stop the Czech Republic winning their second straight Davis Cup trophy, 3-2.

Still, wins No.23 and 24 lifted Djokovic’s spirits after a season in which he won a single major – the Australian Open – and lost top spot in the rankings to Rafael Nadal.

“It’s an incredible number considering the fact that I lost three big matches in three months – Roland Garros (Nadal, semi-finals) , Wimbledon (Andy Murray, final) and the US Open (Nadal, final),” said Djokovic.

“But I managed to bounce back and managed to play my best tennis in the last two and a half months.

“I’m full of confidence on the court and hopefully I can carry that into the next season.”

The 26-year-old said he hoped the streak that brought him titles from Beijing and Shanghai to Paris and London was not over.

“I hope I’ll be able to retain that at the beginning of next season,” said Djokovic, who has clinched four Australian Open titles, and one Wimbledon and US Open trophy. “… I feel I have let escape several grand slam titles which I could definitely have won.”

Djokovic beat Nadal in straight sets at the ATP World Tour Finals in London last Monday.

But he insisted dethroning his top rival was not the key goal for next season.

“For me, grand slam tournaments are the top priority rather than becoming the world No.1 again, although I’m aware that the rankings will come if I win more than two grand slam tournaments next year.”

Even though he lost top spot, some still see him as the world’s top player.

“He’s now the strongest player that’s playing in the world and he proved it today,” world No.7 Berdych said after losing to Djokovic in Belgrade.

“It’s incredible how he can read the game and what sense of the game he has. As if he knew what I’ll play before I take the decision.”

Stepanek shook his head in disbelief at Serbia’s decision not to use Djokovic for the Davis Cup doubles.

“It’s as if they left a Ferrari in a garage. And it cost me 10 euros – I bet he’d play.”