Match detailsFixture: (1) Daniil Medvedev vs (4) Andrey RublevDate: 21 August 2021Tournament: 2021 Western & Southern OpenRound: SemifinalsVenue: Cincinnati, OhioCategory: ATP Masters 1000Surface: Outdoor hardcourtPrize money: $3,028,140Match timing: Not before 1 pm local time, 5 pm GMT, 10.30 pm ISTLive telecast: USA - Tennis Channel | UK - Amazon Prime VideoDaniil Medvedev vs Andrey Rublev previewTop seed Daniil Medvedev will face compatriot Andrey Rublev in the semifinals of the 2021 Western & Southern Open on Saturday.Medvedev played some of the best tennis of his career in the quarterfinals against Pablo Carreno Busta, dismantling the Spaniard 6-1, 6-1. The Russian, who lost to Carreno Busta in the quarterfinals of the Olympics, got off to a blazing start to lead 4-1 in a mere 12 minutes.Medvedev won all of the points on his first serve in the first set. He fared just as well on return, winning every single point on the Spaniard's second serve.Picked a great photo🤣 https://t.co/Bt22Wv5kZe— Daniil Medvedev (@DaniilMedwed) August 20, 2021In fact, the only time Carreno Busta could win a point on his second serve was when he was a couple of games away from defeat.Medvedev, on the other hand, won four of eight points on his second serve and 24 of 26 on his first serve, proving just how lethal that shot was on the night.Andrey Rublev, meanwhile, huffed and puffed his way past mercurial Frenchman Benoit Paire in his last-eight fixture on Friday.Andrey Rublev has his task cut out.Rublev, like Medvedev, got off to a quick start to take the opening set 6-2 without conceding a break point. However, Paire immediately fought back and leveled proceedings by taking the second set 6-3.But the Russian quickly regrouped and was able to secure the decisive break of serve in the eighth game of the decider, before firing back-to-back aces to seal the win.Daniil Medvedev vs Andrey Rublev head-to-headDaniil Medvedev leads Andrey Rublev 4-0 in the head-to-head. What's more surprising is the fact that Rublev has never won a set against his fellow countryman.Daniil Medvedev vs Andrey Rublev predictionDaniil Medvedev has been close to flawless in recent weeks. He is on an eight-match winning streak, during which he has only dropped two sets (both in Toronto).As such, the odds are quite heavily stacked against Andrey Rublev in this fixture. Rublev possesses some of the most powerful groundstrokes on the men's tour, but his tennis IQ is not the greatest and he often struggles to win long rallies.Medvedev, by contrast, enjoys extended rallies in which he can wear down his opponent with his relentless ball-striking. The match-up definitely does not suit Rublev and he is unlikely to pose much of a threat to the red-hot Medvedev.Prediction: Daniil Medvedev to win in straight sets.It's an all-🇷🇺 semifinal @CincyTennis!Daniil Medvedev & Andrey Rublev meet again on the big stage.pic.twitter.com/vbc9Y9IpGB— US Open Tennis (@usopen) August 20, 2021