Danish teenager Holger Rune won his first ATP Tour title after Dutch opponent Botic van de Zandschulp pulled out injured in the first set of their clay-court final in Munich.
The 19-year-old had stunned Olympic champion Alexander Zverev in the second round en route to Sunday’s unexpected triumph.
He quickly trailed 4-1 in the first ATP final for both players, but went on to win the next two matches before van de Zandschulp called the tournament doctor.
He received treatment and walked off the field for several minutes with what appeared to be chest issues, and retired after playing just four more points.
Rune, ranked 70th, became Munich’s second-youngest champion after Guillermo Perez-Roldan, who won it aged 17 in 1987 and successfully defended his title a year later.
The youngster found it hard to believe his extraordinary week-long work after failing to win back-to-back matches at tour level in 2022 ahead of the tournament.
He also beat home favorite Oscar Otte 6-4 6-4 in the two players’ first ATP Tour semi-final on Saturday.
Rune, who also celebrated his 19th birthday on Friday two days after knocking out Zverev, also ousted Jiri Lehecka and Emil Ruusuvuori on the way to his first final.
Later in the Estoril Open final in Portugal, 21-year-old Sebastian Baez also became a first-time ATP Tour winner, earning a straight-sets victory over American Frances Tiafoe.
Baez triumphed 6-3 6-2 in an hour and a quarter against the American, who was playing in his fourth career final.
Baez converted four of five break chances and hit four aces to beat 24-year-old Tiafoe, who struggled with her serve.
Tiafoe had reached the final after beating compatriot Sebastian Korda 4-6 7-6 (7-2) 6-4 after saving three match points on Saturday.