Former top-10 star Mardy Fish pulled out of the U.S. Open on Wednesday due to personal reasons.
The 31-year-old Fish has been trying to make a comeback on tour after battling a heart condition over the last two seasons.
Fish's Twitter feed read, "Friends, unfortunately my health won't allow me to compete this year at the US Open. Thank you for all your support."
Tuesday in Winston-Salem, Fish retired in the third set of his second-round match against Jarkko Nieminen because of heat stroke.
Fish has played only eight ATP matches this year, going 3-5. He will now miss all of the Grand Slam tournaments in 2013.
In March of last year after Fish lost a match in Miami, his heart started to race uncontrollably. Two months later, he underwent a cardiac catheter ablation in Los Angeles to correct faulty electrical connections in his heart, in which those spots were cauterized in order to prevent short circuiting.
The Minnesota native and now Los Angeles resident climbed as high as No. 7 in the world in 2011. He's now down to No. 173.