Daniil Medvedev is eyeing his fifth final in two months after beating fellow Russian Andrei Rublev 6-4 7-5 in the quarter-finals of the St Petersburg Open.

In his first tournament since losing the US Open final to Rafael Nadal, Medvedev will play a semi-final on Saturday against Belarusian qualifier Egor Gerasimov, who beat Matteo Berrettini 7-6 (7-5) 7-6 (7-3).

Before the US Open, Medvedev reached three tour finals in August, winning in Cincinnati but losing in Washington DC and Montreal.

Borna Coric, seeded fourth in St Petersburg, faces qualifier Joao Sousa in the other semi-final.

Coric won his quarterfinal 3-6 7-5 6-3 against Casper Ruud, who had not won a tour-level match indoors until this week.

Sousa upset 2010 St Petersburg champion Mikhail Kukushkin 7-6 (10-8) 6-2.