Alexander Zverev's partnership with eight-time Grand Slam champion Ivan Lendl has yet to pay off at the majors, and the German star is beginning to question his coach's commitment following a first-round defeat at Wimbledon.
Zverev says he's spoken with Lendl about his lack of focus and "told him to concentrate on tennis more."
"Sometimes we go to the tennis court, the training is two hours long, and for half an hour he stands with his back to me talking about the way he played golf the morning before," the 22-year-old told reporters Thursday at the Hamburg Open, according to Tennis.com's Kamakshi Tandon.
Fellow tennis great Boris Becker recently criticized Lendl for his absence at critical points of the season.
Lendl, who notably helped Andy Murray win all three of his Grand Slam titles, didn't travel with Zverev during the clay-court season and won't be with the world No. 5 this week at Hamburg. The former top-ranked junior went just 9-6 on clay leading up to the French Open.
"It did not help that Ivan was not around for the two months before this tournament," Becker wrote in the Daily Mail earlier in July. "You either have your mentor around or you don’t. I do think it is important to surround yourself with people who know what it takes to win a major championship, but it needs to be done properly."
Zverev has been working with Lendl since August 2018 but has been linked with Becker in the past. He'll take on Nicolas Jarry in his first-round match at the Hamburg Open.