A weary Roger Federer will pace himself carefully for the rest of the season, the world No 2 said on Monday.
The five-time US Open champion pulled out of last week's Stockholm Open saying he needed a rest but returns at this week's Madrid Masters.
Federer has not played since helping Switzerland beat Belgium in their Davis Cup World Group playoff three weeks ago.
"I'm still very tired. I felt I just needed some rest. I wasn't sure how much was needed," he told a news conference.
"I took some time off, started practising again, and felt good enough to come and play this tournament. We'll take it from here and go week by week.
"I have had a successful season after winning the US Open so it doesn't necessarily make much sense for me to play that much but I love the game and love to compete. That's why I'm back."
Federer, 27, refused to commit to next week's event in Basel.
"Basel is my home, it's where I used to be a ball boy. I have quite a history there. I've won the last couple of titles and sure I would like to defend it," he said.
"But I am going to take it one week at a time."
Federer said he was also undecided about whether to play in Switzerland's opening Davis Cup World Group match in the US in March.
"Next year's ATP schedule looks much easier because there are no Olympic Games, which gives the calendar a couple of extra weeks," he said.
"I haven't taken the decision yet as regards the Davis Cup first round. I hope I can decide that in the next few weeks as well."
After a first-round bye in Madrid, Federer will meet Czech Radek Stepanek on Wednesday.
(Agencies via China Daily October 15, 2008)