The world number one is the clear favourite to defend his Barcelona Open title and claim his 11th crown at the ATP 500 event but, after a first-round bye, he was less than convincing against Carballes Baena on Wednesday, falling a break behind in the first set.
He recovered swiftly to secure a 6-4 6-4 success and he looked in fine shape 24 hours later as another compatriot was swatted aside 6-1 6-3.
Nadal goes into his quarter-final against Martin Klizan on the back of 16 straight clay-court victories, while he was won each of his last 40 sets on the dirt, and the Spaniard felt the mental side of his game was in a better place against Garcia-Lopez.
“Today I went out on the court with a better mentality than yesterday,” he said. “I had a clear idea of what I had to do to win.
“I made a great first set although I was a bit clueless when I got 4-0 in the second set, the opponent gained confidence and began to play more aggressive.
“I have a good dynamic, winning seven [matches] in a row before arriving here, two in the [Davis] Cup and five in Monte Carlo.
“However, whenever you get to a different tournament, it gives you a bit of a slump. Roberto played very well yesterday, I did not find my game at the beginning of the match.
“I felt very uncomfortable due to his game, I gradually got into the court, improving and taking the victory.”
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