Holger Rune earned the biggest win of his young career when he defeated BMW Open’s top seed Alexander Zverev in straight sets.

The Dane produced a high-class all-court performance against Zverev, breaking the big-serving German four times on his way to a stunning 6-3, 6-2 victory at the ATP 250 event.

Dialed in from the start, Rune surged to a 4-2 lead in the opening set courtesy of some brilliantly measured drop shots from deep.

Zverev found his footing after a slow start and Rune was forced to fend off two break points of his own before converting his sixth set point in a marathon ninth game to take the first set.

An early break in the second set piled even more pressure on the two-time champion while the Dane remained stout at the prospect of upsetting the top seed.

The 18-year-old continued to draw Zverev forward to great effect with his drop shot and struck the ball cleanly off both wings from deep as the German struggled to find his rhythm.

After breaking the German again Rune served out the match for a one-hour, 40-minute victory.

The win over the German is the biggest of Rune’s career and his first over a Top 10 opponent at the fourth attempt.

Holger Rune will take on the World no. 63 Emil Ruusuvuori next, after the unseeded Finn defeated Maxime Cressy, 6-3, 6-3.

Rune has shown glimpses of his talent in 2022, winning his opening match in four of his past five tour-level events before arriving in Munich.

Prior to his loss, home favorite Zverev had not failed to reach the quarter-finals in Munich in his past five appearances, a streak that included lifting back-to-back trophies in the Bavarian city in 2017 and 2018.

He was looking to kickstart a stuttering season.