The 25-year-old Zverev went through his ankle in the semi-final battle against the eventual champion on Friday, in the final phase of the second set. After three hours of play, there was only a second tiebreak, but Zverev screamed in pain and returned to the track fifteen minutes later on crutches.
He was unable to continue playing and announced this weekend that he tore several ligaments in his right ankle.
Zverev was in the final in Halle in 2016 and 2017. In 2016 he lost in the final to compatriot Florian Mayer, a year later Roger Federer kept him from the title.
Wimbledon starts in exactly three weeks.