Emiliano Grillo posted a 5-under-par 67 Thursday at Bay Hill to grab the early lead at the Arnold Palmer Invitational.
Later in the day, Matthew Fitzpatrick matched Grillo with a 67 of his own to share the first-round lead with the Argentinian.
Grillo was 2-over par after four holes, but made seven birdies to finish his round, while the young Englishman made five birdies and no bogeys.
The defending champion, Jason Day, made three birdies and a bogey to post a 70, while Rory McIlroy struggled on the day to card a 74.
Sam Saunders, Palmer’s grandson, went 4-over on the final five holes to shoot a 2-over-par 74.
It was the first time the event has been held without Arnold Palmer, who passed away last September.