SAN FRANCISCO -- The Giants locked up star third baseman Matt Chapman on Wednesday night, announcing a six-year, $151 million contract extension that will keep the four-time Gold Glove winner in San Francisco through the 2030 season.

Chapman will earn $25 million in each of the next six seasons and receive a $1 million signing bonus in 2025. The new deal marks the biggest contract the Giants have handed out since Farhan Zaidi took over as president of baseball operations in November 2018, edging the six-year, $113 million pact former KBO star Jung Hoo Lee signed in December. It’s also the second-richest deal in franchise history, trailing only the nine-year, $167 million contract extension Buster Posey received in 2013.

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Chapman, who is represented by Scott Boras, initially joined the Giants on a one-year, $18 million deal in March, which included player options for ’25 and ’26, as well as a mutual option for ’27. The 31-year-old veteran seemed to be positioning himself to opt out following his strong 2024 campaign, but the Giants managed to hammer out a long-term deal to prevent him from hitting free agency at the end of the season.

Boras clients almost always test the open market, but Chapman has clearly grown comfortable in the Bay Area, where he’s starred for both the Giants and A’s over his eight-year career in the Majors. Chapman also has strong relationships with Giants manager Bob Melvin and third-base coach Matt Williams, which likely helped convince him to stay in San Francisco.

Chapman entered Wednesday batting .247/.333/.445 with a team-high 22 home runs and 6.0 bWAR, tied with the D-backs’ Ketel Marte for the third-highest mark in the National League. It’s Chapman’s highest bWAR since he amassed a career-high 7.8 during his All-Star campaign for the A’s in 2019. The two-time Platinum Glove winner also leads all Major League third basemen with 13 Defensive Runs Saved this year, according to FanGraphs.

Chapman was a late scratch from the Giants’ 6-4 loss to the D-backs on Wednesday night, marking only the fourth time he’s been out of the lineup in 140 games this year. He’ll remain a fixture at third base through the end of this decade, giving the Giants a cornerstone piece to build around as they prepare to turn the page on a disappointing 2024 season and look ahead to 2025.

The Giants are expected to hold a press conference with Chapman, Zaidi, Melvin and Boras at 10:30 a.m. PT on Thursday at Oracle Park to discuss the new deal.