Lille - Roger Federer has suffered his worst career defeat in a Davis Cup live rubber 6-1, 6-4, 6-3 to Gael Monfils, who pulled France level 1-1 in the final with Switzerland on Friday.
Federer, who had been treated all week for a back problem he suffered last Saturday night in London, had never gone down in straight sets in a Davis Cup live rubber. The eight games he won were his lowest ever and compared only to the 10 he won in a tie against Italy as a teenager in 1999.
The world number two still holds a 48-17 record in Davis Cup singles and doubles.
"You accept the fact that you're playing the way you feel," said Federer. "But it wasn't all negative. I started to feel better as the match went on."
Federer said that after overcoming initial anxiety about his back pain, his next problem was a simple lack of court time on the clay.
Despite having a few October training sessions on the surface, the 2009 French Open winner realised that was not going to be enough in the end.
"The problem became that I didn't play on clay much," he said. But he said that was "a good problem for me to have" because it put his back issues aside.
Federer also expressed optimism about his improving condition for the remainder of the weekend. He said he would make himself available if he felt he could "play proper tennis," adding that he felt he was able to do that in the match against Monfils.
"It's not like I couldn't play at all," he said. "In the second set, I was playing to get back into the match. I had the info I was looking for, and I started to relax a little bit and started to feel better as the match went on."
As the match went on, Federer said he started to loosen up.
"I guess I needed to hit 30 big serves, I needed to slide, I needed to be in defense, I needed to play offensive tennis, get information quickly."
The 33-year-old said that after pulling up remarkably well from his exertions, he could even be available for Saturday doubles, a surprise considering his condition last weekend when he pulled out of the London year-end final against Novak Djokovic in pain.
"Right now I feel somewhat all right. Whether [playing doubles] is the right move, I can give my information to [captain] Severin [Luthi] and Stan (Wawrinka) and the team, and then they together will take hopefully the right decision."
With an optimistic nod to the remainder of the weekend, Federer said that he did not expect his back to be a major concern.
"If you have a back issue, it's just one of those feelings [that make you] you feel uncomfortable. You don't have to be in unbelievably excruciating pain, but it takes a while for it to leave your mind," he said.
The match took less than two hours, but Federer was happy that he got three sets in.
"I would think that I'm going to get better as the weekend goes on, which I really hope is the case."