London - Roger Federer has set himself a target of reaching at least 20 Grand Slam titles before he retires.
The 29-year-old Swiss took his tally to 16 with a victory at the Australian Open earlier this year, but he failed to get beyond the quarter-finals at either the French Open or Wimbledon and has dropped to No. 3 in the world rankings, his lowest position since November 2003.
However, despite his recent form, Federer told the BBC that winning 20 majors is "is something doable for me."
Federer, who is regarded by many as the greatest player ever, overtook Pete Sampras' record of 14 major titles in 2009 by winning the French Open and became only the sixth man in history to win a career Grand Slam.