Former world number one Andy Murray secured his first victory over a top-five opponent in six years with a 7-6,(4) 6-3 win over Greek top seed Stefanos Tsitsipas to reach the semi-finals of the Stuttgart Open on Friday.

He will face Australian Nick Kyrgios in the semifinals.

The two-time Wimbledon champion stepped up his preparation for the grasscourt major starting this month by battling through a tight opening set against world number five Tsitsipas before rolling back the years in the second set to complete the win.

The Scot's biggest win by ranking since he overcame Novak Djokovic at the 2016 ATP Finals set up a semi-final meeting with either Hungarian Marton Fucsovics or Australian Nick Kyrgios.

"I thought I did well. He served unbelievably well in the first set and I had very few chances when I was returning," the 35-year-old Murray said in his post-match interview.

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"But when he was creating opportunities on my serve I stayed strong. I played a really solid tiebreak and in the second set, I served well while his dropped a little bit.

"Once I was in the rallies I felt like I was dictating a lot of the points so it was a good performance."

Murray said that he was happy to hit top gear on his preferred surface.

"I don't want to say I was the smarter player, but maybe this surface suits my style. Stefanos plays well on all surfaces but this works really nicely for my game and I'm able to use my strengths better."

Matteo Berrettini, the 2021 Wimbledon runner-up, earlier booked his place in the last four of the ATP 250 event with a 3-6, 6-3, 6-4 win over fellow Italian Lorenzo Sonego.

He next faces local favourite Oscar Otte, who went through following a walkover by Frenchman Benjamin Bonzi.