WATCH—Alexander Zverev's Citi Open championship speech:


Alexander Zverev has confirmed that Ivan Lendl has joined his team as a coach, just before the final Grand Slam of the season.

"Welcome to the team Ivan Lendl," Zverev wrote on social media, with photos of the former No. 1 on the court with him.

"Sascha has a unique set of skills and a great work ethic so I am looking forward to helping him achieve his goals," Lendl was quoted as saying by his agency.

The move comes as 21-year-old Zverev, a three-time Masters champion, attempts to turn around his relatively poor record at Slams—something Lendl is known for himself. He reached four Grand Slam finals before finally winning as a 24-year-old, and also coached Andy Murray to his three Grand Slam titles.

Even a week ago at Cincinnati, Zverev was downplaying Lendl's potential involvement.

"I don't have any coaching changes right now, that's not what I mean, but in the future, yes for sure I think he's someone who can help," Zverev said at the tournament.

The German split with another former No. 1, Juan Carlos Ferrero, towards the beginning of the season, with some public disagreements about what led to the decision. His father, Alexander Sr., is also his coach.

Zverev is No. 4 in the rankings.