Italy's Jannik Sinner (L) talks with former tennis player John McEnroe after a match.(AFP) Last year, the Italian’s US Open title run was under the spotlight due to a doping incident.
Cahill joined Sinner's coaching team in 2022, and the 23-year-old Italian player has since won two Grand Slam events, including the 2024 Australian Open, and has climbed to No. 1 in the ATP rankings.