World number one Roger Federer outlasted Marat Safin in a tie-breaker that matched the longest in tennis history on Saturday to book a date against Lleyton Hewitt in the ATP Masters Cup final.
Defending champion Federer denied the fourth-ranked Russian on six set points but needed eight match points of his own before escaping with a tension-packed 6-3, 7-6 (20/18) semifinal triumph.
"The tie-breaker was very special," Federer said. "I've never played a tie-breaker like it. That was really fun, going back and forth, all big points, match points, set points, and the level of play was high too.
"We were pushing each other to the limits," he said.
Third-ranked Hewitt advanced with no drama at all, the Australian scoring the final 20 points in a 6-3, 6-2 rout of second-ranked American Andy Roddick. Hewitt could win his third Masters Cup title in four years in yesterday's final.
Triple Grand Slam winner Federer won his 16th match in a row and 22nd consecutive triumph over a top-10 rival, the 23-year-old Swiss star fighting off Safin's comeback bid to win in 1hr 47min.
"I'm happy that I kept my act together and finished the tie-breaker well. There was a lot on the line," Federer said. "I had many great saves. My hanging in there made a difference."
The 20-18 record for tie-breakers since they were adopted in 1970 was set in 1973 at Wimbledon when Sweden's Bjorn Borg beat India's Premjit Lall 6-3, 6-4, 9-8 (20/18) in a first-round match.
Also equalling the mark was a 6-4, 7-6 (7/5), 7-6 (20/18) triumph by Croatian Goran Ivanisevic over Canada's Daniel Nestor in round one of the 1993 US Open.
Momentum swung back and forth throughout the tie-breaker, which lasted 26 minutes and 38 seconds until Safin hit his second and final double-fault and then fired a forehand beyond the baseline to end the marathon.
"I was nervous. I was under pressure. Everybody has these moments," Safin said. "I was starting to get to his serve. I put too much pressure on myself trying to win that tie-breaker.
"I was probably going for too much because I knew it was Roger Federer on the other side. I was too excited waiting for a good opportunity and rushing too much."
Safin, who lost to Federer for the sixth time in seven matches, was confident he could carry momentum to victory if he could force a third set.
"I made mistakes but at least I was going for it," he said. "I was enjoying it because I knew if I won the tie-breaker I had a huge chance to win the third set."
The finalists have split 14 prior matches, but Federer is 5-0 against the Aussie this year, ousting him in the Australian Open fourth round, Wimbledon quarterfinals and US Open final in his march to a total of three Grand Slam triumphs.