Switzerland's preparations for the Davis Cup final against France in Lille on Sunday have been disrupted by a back injury to Roger Federer and a spat within the Swiss camp.
The 17-times grand slam champion, chasing the only major title to elude him, withdrew from Sunday's ATP World Tour final against Novak Djokovic citing back problems and skipped training at Lille's Pierre Mauroy stadium on Tuesday.
World number two Federer said his back was "not good enough" to practice on Tuesday, doing little to dispel doubts surrounding his participation in the final, which will be played indoors on clay from Friday to Sunday.
If Federer fails to recover and the Swiss claim a maiden Davis Cup title he would still receive a replica trophy and be considered part of the winning team but only the four players nominated for the final will have their names on the trophy.
"I'm making some progress. But I know I don't have a month ahead of me to get better. I need to get better quickly. I'm trying whatever I can," he said on Tuesday.
Federer is due to spearhead the Swiss challenge just days after being dragged into a row between his wife Mirka and Davis Cup teammate Stan Wawrinka during their World Tour semi-final clash in London.
World number four Wawrinka, who seems back to his best after going through a rough patch, was heckled by Mirka during the match, which Federer won in three sets after saving several match points, but the Swiss camp played down the controversy.
"I believe this makes us even closer to each other. As the two players said, we talked about it," said captain Severin Luthi who can also call on Marco Chiudinelli, the world number 212, and Michael Lammer, ranked 508th.
France's advantage may lie in their strength in depth as all of their players feature in the top 30.
Captain Arnaud Clement, looking to steer the team to their 10th Davis Cup title - although the first since 2001 - must choose his second singles player alongside French number one Jo-Wilfried Tsonga.
Richard Gasquet was instrumental in Les Bleus' defeat of holders the Czech Republic in the semi-final on the Roland Garros clay although the entertaining Gael Monfils has not been at his best since the US Open.
All members of the French team except for Gasquet have already played in a Davis Cup final.
"Of course it is good for us. In a final there is always more emotion, more pressure. Experience is important," said Clement.