Lille - Roger Federer has said on Tuesday that he was "hopeful" he would be able to play in the Davis Cup final against France on Friday despite the crippling back injury he sustained in London.
"I am not good enough to practice yet and I wish my progress would be faster," the Swiss star told a press conference at the Stade Pierre Mauroy outside Lille which will host the three-day final.
"It's a little bit better than on Saturday, Sunday, Monday so I am hopeful."
Federer sustained the back injury playing in the semi-finals of the ATP World Tour finals in London on Saturday evening during a gruelling three set match against Swiss teammate Stan Wawrinka.
The world number two said that the Swiss team's medical staff had been working hard on his fitness and that the pain he had felt on Saturday was easing.
Asked if he was worried about missing the chance to win the Davis Cup final for the first time in his career, he replied: "I don't know. I'm a positive kind of person so I have to believe in it."
Were Federer to miss the final, it would be a huge body blow to Swiss hopes as although Wawrinka at fourth in the world is comfortably ranked above all the French players, after him the fall off in the Swiss team is steep with Marco Chiudinelli 212th and Michael Lammer 508th.
Federer and Wawrinka earlier took to Twitter in a bid to bury any lingering resentments from their at times bad-tempered London match.
"It's great being with the boys again," tweeted Federer, above a Swiss team picture including himself and Wawrinka with arms around each other. In the shot, world number four Wawrinka makes playful 'bunny ears' behind his team-mate's head.
That frivolity seemed light years from the fallout that hit the two countrymen as Federer defeated Wawrinka 4-6, 7-5, 7-6 (8/6) on Saturday evening in the ATP World Tour Finals semi-finals.
Federer had saved three match points in the 10th game of the deciding set in that match and it was poised at 5-5 and 40-40 in game 11 when Warwinka gestured to Federer's box asking that they not make noise in between serves.
Federer's wife Mirka was sitting in the players section and he was reportedly upset that Wawrinka had blamed her.
The two were then seen involved in a long and tense discussion in the locker-room after the match and on Monday each went their own way en route from London to Lille in northern France for the Davis Cup showdown.
The London dogfight between the Swiss, the intensity of which astonished many people in France, has cast a cloud over the Swiss hopes.
In stark contrast it has been all plain sailing for the French who are seeking a 10th Davis Cup title in all and a first since 2001.
Captain Arnaud Clement cloistered his team of Jo-Wilfried Tsonga, Gael Monfils, Richard Gasquet and reserve Gilles Simon, none of whom qualified for the London finals, in Bordeaux where they honed their claycourt skills away from prying eyes.
The French as hosts have chosen an indoor claycourt as the surface for the final believing that gives them a better chance of defeating the two higher-ranked Swiss players.
Doubles specialist Julien Benneteau, who was playing in the doubles in London, then linked up with them after they decamped to Lille.
Clement said that the French camp were not even considering contesting the Davis Cup final without the presence of Federer.
"We have been preparing for the last 10 days to play against a French team with Federer and Wawrinka in it," he said.
Clement said that he had yet to decide who would play the opening two singles on Friday but Tsonga looks sure to be top choice with Gasquet slightly ahead of Monfils for the second slot.