Juan Martin Del Potro denies he committed tax evasion in his native Argentina, a spokesman told the Associated Press.
The Argentine newspaper Perfil reported on Sunday that authorities were investigating Del Potro for possible tax evasion. The investigation reportedly concerns his 2010 tournament winnings.
Del Potro has not played since undergoing wrist surgery in March. He pulled out of the U.S. Open last week.
The 25-year-old won the U.S. Open in 2009, his only career Grand Slam victory. He is currently ranked No. 13 in the world.
- Dan Gartland