SAN FRANCISCO -- A Giants debut won’t be in the cards for speedster Billy Hamilton, who was traded to the Mets on Sunday in exchange for pitching prospect Jordan Humphreys.

Hamilton signed a Minor League deal with the Giants in February and entered Spring Training as the club’s most established center-field option, but he was left off the Opening Day roster after reporting late to Summer Camp for undisclosed medical purposes.

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Mike Yastrzemski has started all but one game in center field thus far and has proved to be a solid defender. Manager Gabe Kapler has said the Giants want to maintain a sense of continuity for Yastrzemski, who entered Sunday hitting .400 (12-for-30) with two home runs over nine games.

Steven Duggar, who was added to the 30-man roster on Tuesday, and Mauricio Dubón are also center-field options for San Francisco, leaving little playing time for Hamilton at the big league level.

“Our roster evolved, and we recognized the value of having extra bats and extra arms in the ‘pen,” Kapler said Sunday. “That just kind of made Hamilton a tougher fit, particularly with us going down to a 28-man roster size later this week. He's done a really nice job in Sacramento for us, and we see the value to the Mets and the situation they have right now.”

Humphreys, a 24-year-old right-hander who was ranked the Mets’ No. 14 prospect by MLB Pipeline, will report to the Giants’ alternate training site in Sacramento. An 18th-round Draft pick of the Mets in 2015, Humphreys missed the entire 2018 campaign after undergoing Tommy John surgery. He returned at the end of last season and demonstrated he was healthy during an impressive stint at the Arizona Fall League, where he logged a 0.77 ERA over 11 2/3 innings and earned a Fall Stars Game selection.

Humphreys showed that he had regained his pre-surgery velocity, with his fastball sitting in the low 90s and topping out at 94 mph. He also throws an above-average, upper-70s curveball as well as a changeup. Aside from his AFL experience, Humphreys has not pitched above Class A, but he’s recorded a 2.60 career ERA over four Minor League seasons.

“He had a lot of carry through the zone before Tommy John,” Kapler said. “He still has a lot of carry through the zone. He's a strike-thrower, and a real prospect for the Mets. We're excited to have him.”