Alexander Zverev upset at BMW Open, Holger Rune advances

FLASHBACK: Christopher O’Connell defeats Denis Kudla in the 2021 Atlanta Open first round.

After waiting an extra day to get on court at the BMW Open, Alexander Zverev's tournament was ended in straight sets by Christopher O'Connell on Thursday as top-seeded Holger Rune won his opening match.

Zverev had a first-round bye and his second-round match with O'Connell was delayed a day after rain washed out most of the Wednesday schedule.

Playing 82nd-ranked O'Connell in cold conditions in front of a German crowd huddled in thick coats, Zverev never built much momentum and struggled to land his first serves as he was defeated 7-6 (2), 6-4.

"It's definitely tough playing Zverev here in front of the home crowd," the 28-year-old Australian said in his on-court interview. "This is the coldest weather I've ever played in. It's tough, took me a while to get warmed up."

O'Connell will play qualifier Flavio Cobolli in the quarterfinals.

Rune secured a spot in the quarterfinals with a 6-3, 6-4 win over Yannick Hanfmann and next plays Chilean clay-court specialist Cristian Garin. Rune is aiming to follow up his strong start to the clay season after he was runner-up to Andrey Rublev in Monaco last week. Garin beat sixth-seeded Lorenzo Sonego 6-3, 7-6 (3).

There were wins too for the second-seeded Taylor Fritz, who beat Marton Fucsovics 4-6, 6-3, 6-3, and fourth-seeded Botic van de Zandschulp, who defeated Aslan Karatsev 6-2, 6-0.

Dominic Thiem's match with Marc-Andrea Huesler was suspended because of darkness. The winner faces Fritz in the quarterfinals.