Three-time World Series champion Sergio Romo is retiring after 15 seasons in Major League Baseball.

Romo pitched his final game on Monday night for the San Francisco Giants in the Bay Bridge exhibition against the Oakland Athletics.

The Giants signed Romo to a minor-league contract with an invite to big-league camp on March 18.

Per The Athletic's Andrew Baggarly, the plan was to build Romo's arm strength and conditioning to appear in one or two spring games, culminating with the right-hander making one final appearance at Oracle Park vs. the A's to retire in front of the team's fans.

Romo allowed one run on two hits and one walk. Hunter Pence, who played with Romo in San Francisco for five seasons from 2012 to '16, emerged from the dugout to make the call to the bullpen and give his former teammate one final send-off.

The 40-year-old Romo was a 28th-round draft pick by San Francisco in 2005. He made his MLB debut with the team three years later and was an integral part of the bullpen during their three World Series runs in 2010, 2012 and 2014.

In 515 regular-season games with the Giants, Romo had a 2.58 ERA, 0.96 WHIP and 498 strikeouts in 439.2 innings. He posted a 1.02 ERA in 19 appearances over two playoff appearances in 2012 and 2014, including recording the final out of the 2012 World Series against the Detroit Tigers by striking out Miguel Cabrera.

Romo also had stints with the A's, Minnesota Twins, Tampa Bay Rays, Los Angeles Dodgers, Seattle Mariners, Miami Marlins and Toronto Blue Jays in his career. His final appearance in a regular-season game was on July 14, 2022, for the Blue Jays in a 3-1 loss to the Kansas City Royals.