STUTTGART, Germany — German 17-year-old Justin Engel became the youngest player since Boris Becker 40 years ago to reach the quarterfinals of an ATP Tour grass-court tournament by making the last eight at the Stuttgart Open on Thursday.

Engel beat seventh-seeded Alex Michelsen of the United States 6-4, 6-4 to become the youngest quarterfinalist ever in Stuttgart. He is the youngest man to reach the quarters of any grass-court event since Becker won Wimbledon as a 17-year-old in 1985.

Engel, who turns 18 in October, will next face Félix Auger-Aliassime of Canada on Friday.

It has been a remarkable 12 months for Engel, who only broke into the top 800 in the rankings last July, having entered the 2024 season as No. 1,344. He is now guaranteed to move into the top 250.

Engel this week also became the second youngest player since 1990, behind Rafael Nadal, to have won a match on all three surfaces — grass, clay and hard-court — on the tour.