NEW YORK, Sept 2 (Reuters) - Alexander Zverev thrashed Spain"s Albert Ramos-Vinolas 6-1 6-0 6-3 in a brisk 74 minutes on Thursday, conserving his energy as he rolled through to the third round of the U.S. Open. More than half of the German"s serves went unreturned in the lopsided affair, after Zverev got a break to kick off the first set and never let up the momentum. The world number four fired down 11 aces, including three in a row to close out the third set on Arthur Ashe Stadium where he came within two points of triumphing a year ago before losing the final in heartbreaking fashion to Austrian Dominic Thiem. "It was painful and I still remember it," said the newly-crowned Olympic champion. "I take it as motivation because I"m back here, I have the opportunity to do better." After picking up Masters titles in Madrid and Cincinnati this year, the 24-year-old is among a cohort of younger players hoping to disrupt world number one Novak Djokovic"s bid for a calendar-year Grand Slam. "It"s great that I"m through in three sets," said Zverev. "I will need that energy, I will need the power."