[1] Agbayani made his major league debut with the New York Mets on June 17, 1998, as part of an 8th-inning double-switch in which he defensively replaced center fielder Butch Huskey during a 5–4 loss to the Montreal Expos.

Agbayani, thinking that the catch made three outs, gave the ball to a child, Jake Burns, in the stands and began to trot toward the dugout.

Upon realizing his mistake, Agbayani sprinted back to the stands, pulled the ball from the hands of Burns, and fired a throw toward home plate.

Unfortunately for Agbayani, once the ball left the field, the play was dead, and all three runners were awarded two bases—causing Jeff Kent and Ellis Burks to score, and the Giants to take the lead, 2–1.

[4] Agbayani is also fondly remembered by Mets fans for two clutch home runs hit during the 2000 season, earning him the nickname "Hawaiian Punch" (after the popular fruit drink).

Later that year, on October 7, he hit a game-winning home run in the 13th inning of Game 3 of the National League Division Series against Aaron Fultz of the Giants.

The Boston Red Sox selected Agbayani off waivers from the Rockies on August 26, 2002, as the club made a drive for the playoffs.

In his final MLB game, September 29, Agbayani went 1-for-4 with a walk and a strikeout as the Red Sox defeated the Tampa Bay Devil Rays at Fenway Park.

[11][12] After graduating from Cal in the spring of 2023, she is pursuing master's degree in public health at Brigham Young University and playing softball in the 2024 season.