Mardy Fish made a winning return to tennis in the opening round at Wimbledon on Tuesday - his first match following a procedure to address a frightening heart scare.
The world number 12 beat Spain's Ruben Ramirez-Hidalgo 7-6 (7/3), 7-5, 7-6 (7/1) and looked comfortable moving around the court.
It was his first tournament appearance since April, when, as top seed, he fell at the first hurdle in Houston.
He had a procedure called cardiac catheter ablation in Los Angeles on May 23 to correct faulty wiring in his heart.
Fish said the arrhythmia had made it hard for him to sleep and his heart felt like it was going to burst out of his chest.
Fish is the top American left in the draw after world number 10 John Isner was knocked out on Monday.
During his two-hour, 37-minute match on the Court 12 show court against Ramirez-Hidalgo, the world number 82, Fish sent down 24 aces and hit 61 winners.
He was at ease in the third set tie-break, sealing his victory with a cross-court return of serve for his first win since Miami in March.
Spanish number 10 Ramirez-Hidalgo was the oldest player in the men's singles at 34 years and six months. He has never won a match on grass and has won just one tour-level match this year.
Fish, by contrast, is a comfortable performer on the surface, has a grass court title to his name (Newport 2010) and only six other men competing here have won more singles matches on grass than him.
Last year, Fish equalled his best Grand Slam result by reaching the quarter-finals, where he lost to Rafael Nadal.