Former world no. 1 British Andy Murray has withdrawn from the French Open in order to ramp up his preparations for the grass-court season in the build-up to Wimbledon, which starts on July 3.
Zverev has not played since hurting his ankle at the French Open in early June and after surgery remains a doubt for the US Open, which takes place directly before the Davis Cup.
World No 5 Rafael Nadal clinched his 14th French Open title of his career which was also his record-extending 22nd Grand Slam trophy after beating Casper Ruud 6-3, 6-3, 6-0 in the final of the tournament, on Sunday.
By earning a 22nd Grand Slam crown, the Spaniard has moved further clear of Novak Djokovic and Roger Federer in the Grand Slam race, with the Serbian and Swiss tied on 20 major titles.
Under the roof on Court Philippe Chatrier, one of the biggest matches of the season was cut short at 7-6(8), 6-6, when Zverev had to leave the court on a wheelchair after he badly rolled his right ankle, moving to his right when tracking down a Nadal forehand deep behind the baseline.
On Saturday, Djokovic defeated Galan 6-0, 6-3, 6-2 to improve to 71-14 in French Open grand slam.
The French Open was initially scheduled to take place from May 24 to June 7 but due to the outbreak of the virus, it was postponed till September 20.
Despite his maiden victory in Monte Carlo, however, Nadal wasn't sounding confident about his chances at Roland Garros later that season.
Murray goes on to face France's world number 70 Ugo Humbert who put out Argentine fifth seed Guido Pella 5-7, 6-4, 6-4.
Meanwhile, Serbia's Novak Djokovic and Spain's Rafael Nadal have also confirmed their participation in Tokyo 2020.
