World No. 63 Tsitsipas, who was facing Nadal for the first time, did not get the better of the Spaniard, in terms of smart moves. The Spaniard served at 71% and despite some troubles on his second serve he kept his service games intact, fending off all three break points (all in the fourth game of the second set when he was already 6-2 3-0 up) to keep the pressure on Tsitsipas and winning 56% of the return points to create 10 break chances.
Tsitsipas may have only won his first match on clay last week in Monte-Carlo but Nadal - who enjoyed his 400th victory on the surface in the semi-finals against Goffin - still views him as a major threat.
But he could not find the consistency to offer more than a fleeting challenge to Nadal, whose next goal will be the Madrid Masters, where he has only won five titles.
"It's very hard to describe how to win 11 titles at one tournament".
"Stefanos is a great player", Nadal said. "Del Potro is also a good clay-court player as well, so perhaps he can do it because he has certainly been hitting the ball beautifully".
Tsitsipas had nothing to lose against the reigning world number 1.
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William and Kate's third child was born Monday, a brother to 4-year-old Prince George and Princess Charlotte , who is nearly 3. William and Kate shared the name with the Queen and the rest of their family before making it public.
Italy's Marco Cecchinato claimed his maiden ATP Tour title with a 7-5 6-4 victory over John Millman in the Hungarian Open final. The 19-year-old was also the youngest player to reach the Barcelona final since Nadal did so in 2005 aged 18.
'I have watched millions of his matches on clay, ' he added. "I'm going to go out there, enjoy it and play my best".
Six days after being knocked out in the qualifying round, Italian 25-year-old Marco Cecchinato on Saturday made the most of a reprieve to reach the Hungarian Open final.
"It is very odd, because I lost last week [in qualifying] and tomorrow I will play the final", said Cecchinato, who earned a place in the main draw as a "lucky loser" after Serbia's Laslo Djere pulled out. "I know Andreas very well because we are friends, I have practiced with him for so many years".
The Spanish great takes the semifinals meeting in straight sets.