Daniil Medvedev’s grass-court season got off to a bad start after the top-seeded Russian lost his first-round match at the Halle Open to Jan-Lennard Struff on Tuesday.

Medvedev was broken three times in a 7-6 (6), 6-3 loss. He was coming off reaching the French Open quarterfinals last week. Medvedev has yet to reach a tour final on grass and hasn’t gone beyond the third round at Wimbledon.

Struff goes on to play qualifier Marcos Giron in the second round.

Germany's  Alexander Zverev  returns the ball during his ATP Tour Singles, Men, 1st Round tennis match against Germany's Dominik Koepfer in Halle, Germany, Tuesday, June 15, 2021. (Friso Gentschdpa via AP)

Germany's Alexander Zverev returns the ball during his ATP Tour Singles, Men, 1st Round tennis match against Germany's Dominik Koepfer in Halle, Germany, Tuesday, June 15, 2021. (Friso Gentschdpa via AP)

Sixth-ranked Alexander Zverev came through his first-round match 6-4, 3-6, 6-3 against Dominik Koepfer. He moves on to face Ugo Humbert after the French player downed Sam Querrey 4-6, 7-6 (4), 7-6 (5).

Andrey Rublev didn't face a single break point as he won an all-Russian match against Karen Khachanov 6-3, 7-6 (5). His second-round opponent is Australian Jordan Thompson.

Félix Auger-Aliassime earned a second-round match against 10-time Halle champion Roger Federer with his 6-3, 7-5 win over of Hubert Hurkacz.

Lloyd Harris managed another upset win as the South African beat eighth-seeded Gael Monfils 6-4, 6-4 to set up a second-round meeting with qualifier Lukas Lacko.

Kei Nishikori booked his spot in the second round after beating Ricardas Berankis 6-3, 2-6, 6-2.

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