Nadal, who won the Monte Carlo Masters for a 10th time last week, romped to the title without dropping a set on the newly renamed Rafa Nadal court at the Real Tennis Club in Barcelona, and needed just 90 minutes to finish off Thiem.
Thiem had beaten the 14-times Grand Slam champion on clay in the Argentina Open last year and earned a place in the final by beating world number one Andy Murray for the first time in his career on Saturday, but he proved no match for Nadal.
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The Mallorcan took a while to impose himself on Thiem on an overcast day in Barcelona with the cold weather slowing down the court.

Rafael Nadal gewinnt zum zehnten Mal in Barcelona

Image credit: Getty Images

Thiem earned the first breakpoint of the match but Nadal recovered and eventually took the first set by breaking his opponent in the 10th game.
There was no let-up in the second set from Nadal, who broke the 23-year-old Austrian twice in a row before serving for the championship and wrapping up his 51st tournament win on clay.
"I'm especially happy for these 10 victories in two tournaments that are as special to me as Monte Carlo and Barcelona, especially here as it's my club, and for the support of these incredible fans," Nadal told Spanish network TVE.
"It's a dream start to the claycourt season."

Rafael Nadal gewinnt zum zehnten Mal das Turnier in Barcelona

Image credit: Getty Images

Thiem paid tribute to his opponent after Nadal's 71st tournament win in his career.
"First of all congrats to Rafa, 10 titles here and in Monte Carlo, it's unbelievable," he said.
"I really enjoyed the week in Barcelona. There are worse things than to lose against the greatest player on clay ever. I enjoyed it even though I lost and I really hope I can come back in the next years."
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