Haas rallied from a 5-2 deficit in the third set to beat Philipp Kohlschreiber 2-6, 7-6 (5), 7-6 (3) in an all-German semifinal at this Wimbledon tuneup. Haas, ranked No. 2 in 2002 but now No. 41, will be playing his first final since winning in Memphis, Tenn., in 2007.
Djokovic lost his two previous matches against Rochus in 2005. He appeared unsure of his footing at the start of the second set, slipping several times. The second-seeded Serb once ended up on his back under the net.
Djokovic double-faulted on his first match point. The Belgian then smashed a winner after the two traded drop shots. But a forehand winner on his third match point gave Djokovic a place in the final.
"I had to work hard for my points, especially on his serve," Djokovic said. "He has a great touch; he rarely makes mistakes from the baseline. I served well and I tried to change the pace."
Djokovic, ranked No. 4 and with two titles this year, has beaten Haas in the two times they have played. This is Djokovic's second final on grass, after Queen's Club last year.
Kohlschreiber was runner-up in Halle last year -- after beating Haas in the second round -- and appeared headed to his second straight final at the tournament.
He was serving for the match while leading 5-3, but he dropped serve in a sloppy game that allowed Haas back into the match. Haas won the first four points of the tiebreaker and served his 15th ace on his third match point.
"I was very surprised myself when it happened," Haas said. "I felt he had had the upper hand and that he could have finished me off earlier."
Added Kohlschreiber: "I felt tight, got a bit nervous. I made a couple of errors and he returned very well."
Kohlschreiber is the top German at No. 24. He enjoyed his best showing at the French Open in seven years when he reached the fourth round. He lost to eventual champion Roger Federer after winning the first two sets.
The 31-year-old Haas has been slowed by injuries since reaching his No. 2 ranking. He had his third shoulder operation in 2007.
Haas said the sunshine after wet, cloudy days created shadows on the court that bothered him at the start.
"I was really irritated," he said. "I was thinking of too many things."