The second-seeded Ruud won 6-3, 6-1 against Benoit Paire to confirm his status as the favorite to retain his title after second-ranked Daniil Medvedev was beaten Tuesday by Richard Gasquet.

Third-seeded Denis Shapovalov also lost his opening match, 6-4, 6-7 (2), 6-3 against Ilya Ivashka.

In a match with few break points, Ivashka saved the only one he faced against Shapovalov and converted one chance in each of the two sets he won.

Ivashka will next face unseeded Joao Sousa who won 6-4, 6-3 against fifth-seeded Nikoloz Basilashvili.

Seventh-seeded Federico Delbonis fell to a 1-6, 7-5, 7-5 loss against Thanasi Kokkinakis, who will face Ruud in the quarterfinals Thursday.

Fourth-seeded American Reilly Opelka ended a streak of early tournament exits in Munich, Madrid and Rome by beating Australian qualifier Christopher O'Connell 6-3, 7-5.

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