Alexander Zverev reached his 18th Masters semi-final in Rome on Wednesday but only after a worrying fall which sparked memories of the horror injury he suffered at the French Open two years ago.

The world number five from Germany defeated Taylor Fritz 6-4, 6-3 to set up a last-four duel with Alejandro Tabilo, the Chilean journeyman who had stunned Novak Djokovic earlier in the tournament.

Zverev's moment of concern came in just the third game on centre court at the Foro Italico when he fell on the clay and landed on his front.

The 2017 champion cut his left wrist and a finger in the tumble and required treatment from the tournament physio before he continued the match.

Zverev, 27, suffered a serious ankle injury at the 2022 French Open after falling on the clay of Roland Garros during his semi-final against Rafael Nadal and missed the rest of the season.

On Wednesday, however, he was able to dust himself down to defeat Fritz in 90 minutes, firing 20 winners with six aces and not facing a single break point.

Chile's Tabilo will play his first-ever Masters 1000 semi-final at the age of 26, after seeing off unseeded Zhang Zhizhen of China 6-3, 6-4 in one hour and 26 minutes.

Women's second seed Aryna Sabalenka needed just an hour and 13 minutes to see off Jelena Ostapenko 6-2, 6-4 on her way to the semis, improving her record against her Latvian opponent to three wins and no defeats.

Sabalenka will next take on Miami Open winner Danielle Collins who eased past Victoria Azarenka 6-4, 6-3.

The 26-year-old could get a rematch of the Madrid final which she lost in dramatic fashion to world number one Iga Swiatek earlier this month.

Rome is the first time since the 2013 French Open that the top three women have reached the last four of a WTA event of 250 level or higher, with Swiatek and world number three Coco Gauff in the other semi-final on Thursday. (AFP)