Darren Cahill Has Coached Different Players, but Gets the Same Winning Result

Simona Halep is the third player Darren Cahill, left, has coached to a No. 1 ranking.Darren Cahill is one of tennis’s leading television analysts, but first and foremost he is one of its leading coaches.

His father, John, was an Australian rules football coach, but Cahill gravitated to a different sport. He reached No. 22 in the world in singles and made the semifinals of the 1988 United States Open, and he has now guided three different players to the No. 1 ranking in singles.

His first star pupil was a young Lleyton Hewitt, who, like Cahill, came from Adelaide, Australia. The next was Andre Agassi, whom Cahill helped thrive in the later stages of Agassi’s career. Cahill’s latest project is…