The Serb, who has won the tournament six times, took the first set 6–3, but then the Dane took over.

Rune won the second set with the same numbers and took home the decider with 7–5.

In doing so, he became the youngest winner since Boris Becker won the tournament in 1986 and enters the top ten when the new world rankings are presented on Monday.

Holger Rune is the fifth player this year to win a Masters tournament for the first time.

Two weeks ago, Rune won the Stockholm Open.

Then ranked 27th in the world, in the final he beat top seeded world number five Stefanos Tsitsipas 6–4, 6–4.

CUT: Strange pictures of the 18-year-old;

"It hurt to see" (November 4):

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Cori Gauff was responsible for several strange actions in the night's WTA final.

Photo: C More