While Rafael Nadal continued his impressive comeback to reach the BNP Paribas Open final, Novak Djokovic made a shock exit in Saturday’s semifinals as his winning streak of 22 matches came to an end.

The top-seeded Serb squandered a 3-0 lead in the final set before losing concentration and the match, 4-6, 6-4, 6-4 to Argentina’s Juan Martin Del Potro, on a sweltering afternoon at the Indian Wells Tennis Garden.

Djokovic, a twice champion here, was broken twice in that third set as Del Potro booked his place in Sunday’s final against world number five Nadal, who overcame Czech Tomas Berdych 6-4, 7-5 in a semifinal of high quality.

“It happens,” a gracious Djokovic told reporters after losing for the first time since his defeat last October to big-serving American Sam Querrey in the second round of the ATP Masters 1000 event in Paris.

“All the credit to my opponent today. He deserved to win because he was more composed in the important moments and he played the right shots. I didn’t deserve to win today. You know, whenever I had chances, in the second or third sets, I throw them away with some unforced errors. My movement was poor, and I congratulate to my opponent.”

Earlier, twice champion Nadal made light of his seven months out last year due to a knee injury as he outplayed the sixth-seeded Czech.

The Spanish left-hander, who returned to the ATP circuit only last month, broke his opponent once to take the opening set, then won a tense second set to improve his record this year to a career-best 16-1. “For me this is totally unexpected to be in the final,” smiled Nadal after winning the last four games to come from 3-5 down in that second set.

“But here we are today, and I’m very happy about all what happened the last month, especially the last three weeks.