HALLE, Germany (AP) — 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.

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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