Tsitsipas, who reached the Australian Open semi-finals last month, battled hard to clinch victory over the 31-year-old Kukushkin in a little under two hours.
The 20-year-old, who did not drop a set in the entire tournament, fired 14 aces and won 86 percent of his first-serve points. Tsitsipas said, as quoted by the ATP Tour website:
Winning titles is the thing that I am working for. It's the biggest satisfaction and the biggest joy in tennis.There was a lot of stress this week because I knew I had to face some good opponents. I'm happy that I got through that stress and played the game that I was supposed to play. I lost the spark (after the Australian Open) and I was frustrated because it felt like I couldn't find it again. This week, I can say I am really happy because I felt this hunger back again."
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Break points were in short supply in the opening set with neither player wilting under the pressure as they held serve. However, Tsitsipas drew first blood when he broke Kukushkin at 6-5 to take the first set.
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Tsitsipas was seeing the ball very well on Kukushkin's serve and returns, hitting some juicy forehand and backhand winners straight down the line.
Kukushkin broke Tsitsipas for the first time in the second set and had the chance to break him again to go 5-2 up but the Greek number one saved two break points to mount an epic comeback.
Changing strategies in the second set, Tsitsipas attempted a serve-and-volley game and came up to the net often in a bid to upset Kukushkin's rhythm.
Tsitsipas then won three games in a row to race to a 6-5 lead and was one game away from winning the title before Kukushkin enforced a tiebreak.
The tiebreak went with serve until Tsitsipas broke Kukushkin at the 11th point to set up the win on serve and take home the title, his second after he won the Stockholm Open in October last year.
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