The victory was O'Brien's fourth in five years as Love, ridden by jockey Ryan Moore, pulled clear in the closing stages to beat Cloak of Spirits (12-1) by more than four lengths while the 11-4 unbeaten favourite Quadrilateral finished third.
"She's a very uncomplicated filly. She's a typical Galileo filly," Moore said in a post-race interview with ITV.
"If it wasn't for her last run, last year, you'd have been pretty confident that she was the one to beat today and she was in control of the race from a long way out. She won as she liked, really."
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The race was run without spectators while jockeys and support staff wore face masks.
On Saturday, Qatar Racing-owned 10-1 shot Kameko, ridden by champion jockey Oisin Murphy and trained by Andrew Balding, ended red hot favourite Pinatubo's unbeaten run to win the 2,000 Guineas in record time. (Reporting by Rohith Nair in Bengaluru, editing by Pritha Sarkar)
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