Roger Federer put a brave face on and said he was "happy" despite missing out on a place in the Paris Masters final as he lost to Novak Djokovic in the semi-finals on Saturday.
The world No 3 pushed Djokovic, who will become world No 1 again on Monday, hard in a 7-6, 5-7, 7-6 loss.
It leaves the 20-time major winner still on 99 career ATP titles but he believed he could be encouraged by pushing his Serbian rival, who has not lost a match since August, so hard.
"For the most part I can be happy, my level was good, but losing is never fun," said Federer. "It's intense, it's good tennis, we care about winning, we don't like losing. I can tell you that right now. Novak is obviously on a roll. You can feel it."
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Djokovic has now won 22 matches in a row and is favourite to lift a record-equalling fifth Paris title on Sunday when he faces Russian Karen Khachanov, with the action due to start at 6pm UAE time.
Djokovic, who had complained of competing with flu-like symptoms in his previous matches this week, was proud and relieved to repel a wonderful challenge from Federer, who appeared close to his imperious best.
"We've had epic matches throughout our rivalry but this one definitely ranks as one of the best matches we played. High quality tennis," Djokovic told reporters.
"Next to the match I played against (Rafa) Nadal in the Wimbledon semis, this was definitely the most exciting match I've played this year, and probably the best quality match that I was part of."
Even though he was not broken once, it was still not enough for the 37-year-old Swiss, whose nerve failed him in an anti-climactic final tiebreak in which he served a double fault and made two more careless groundstroke errors.
Ultimately, though, Federer, who saved all 12 break points on his serve, saw his resilience ended as Djokovic extended his career lead over the Swiss to 25-22 after their longest-ever three-set duel.
It was the first time in their 12 years of battling that Djokovic had won four matches in succession against Federer, equalling the run that the Swiss himself had once achieved at the dawn of their rivalry.