Roger Federer was proud to regain his world number one status last year and wants to stay top of the rankings for as long as he can, he said on Monday.
The 28-year-old Swiss leapfrogged Spain's Rafael Nadal at the top of the rankings thanks to his 2009 victories at Wimbledon, the French Open and the Cincinnati Masters.
"I would like to stay the top player in the world... because going from number two to number one was hard work and not an easy thing to do especially with Rafa playing so well," Federer told reporters ahead of his Qatar Open title challenge.
"That was a major accomplishment for me and I would like to stay there as long as possible and try to finish 2010 as world number one."
The 15-times grand slam champion believes he can achieve even better results than he did last year.
"I think I can definitely, if my body allows me, win many more tournaments than I did in 2009," said Federer ahead of Tuesday's first-round meeting with Belgian Christophe Rochus. "I really just had to focus on the major events last year.
"I hardly played any smaller events but if I'm healthy this year I can win many more tournaments and that could also help get me more confidence, more momentum."
Federer said a feature of his previous spell as number one was the decision he made to be selective about which tournaments he played.
"It's important to listen to your signals," he said. "I think that's one thing I did really well when I became number one.
"I had all the things going for me and huge opportunities to go and chase money or tournaments around the world but I said I'm not going to do it.