The 32-year-old former world number one slipped to number six in the rankings at the end of 2013 following a mid-season back injury and a series of disappointing results, particularly in the Grand Slams.
He won just one title in 2013, and failed to make a major final for the first time since 2002. However, Federer warned against writing him off, saying the recent appointment of Stefan Edberg to his coaching staff was an indication he still had the desire to compete at the top level.
“Critics are part of the tennis game, and they will be the last ones to put me out of the game,” Federer said on his arrival here. “I still have a lot to do. Considering everything, I finished the season sixth, which was unbelievable.”