Roger Federer is retiring from professional tennis.

Barely a month after Serena Williams announced her retirement

41-year-old Federer took to Twitter to announce

next week’s Laver Cup in London will be his last ATP event.

Roger Federer won 20 Grand Slam singles titles

A knee injury meant he has not played a match

Roger Federer  played more than 1,500 matches over 24 years.

Federer is behind only Spain's Rafael Nadal (22) and Serbia's Novak Djokovic (21), on the list of most men’s singles Grand Slams. 

Federer had offered some hope to his legions of fans

Federer first served notice of his special talent when he beat American great Pete Sampras