The defeat means Zverev will drop to fourth, with Roger Federer taking his No. 3 ranking on Monday. Federer plays at the Madrid Masters next week. Garin next faces third-seeded Marco Cecchinato, who rallied to beat Marton Fucsovics of Hungary 1-6, 7-5, 7-5. He saved one match point.
Matteo Berrettini defeated three-time champion Philipp Kohlschreiber 4-6, 7-5, 6-4 and will face fourth-seeded Roberto Bautista Agut, who also fought back and beat Guido Pella 4-6, 6-4, 6-0.
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