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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“Thinking back to why we were so excited to bring Matt here in the first place, I think he’s delivered all that and more just in terms of our goals this past offseason of adding more consistency to the lineup, upgrading our defense, just having a guy who can be a leader on and off the field,” Zaidi said during a press conference at Oracle Park on Thursday. “We just got to the point where it was hard to imagine the Giants in 2025 and beyond without Matt Chapman at third base.”

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.

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“This last offseason was a little strange with the free-agent market, but I was willing to bet on myself,” Chapman said. “I believed in myself and believed that the Giants would see my value as the season went on and what I bring every single day. Just trying to win baseball games and be a good teammate and give everything that I have. I’m excited to give everything that I have for these next seasons, and we’ll see where it takes us.”

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.

“This feels like home for me,” Chapman said. “It feels like I’ve been here for a lot longer than one season. … I feel really comfortable in the Bay Area, and I just love being here.”

“I think in this case, Matt made it clear to me all along that he had every piece of information we could give him and he knew what he wanted to do,” Boras said. “For me, that’s the most rewarding part. Matt really made a choice, and he’s happy about where he wants to play and who he wants to play for.”

Chapman entered Thursday slashing .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.

“The performance speaks for itself, but I think it’s a lot of the intangible things that kind of make him who he is and make him such a great fit here,” Melvin said. “The style of play, the tenacity with which he plays. He wants to play every single day. He plays hurt and never says anything about it. When you have your best players and your leaders playing a certain way -- we have some younger players here that are learning their way and developing right now, and they watch the way he plays the game. There’s an expectation of how it needs to be played, and when he’s setting the example for that, guys have to fall in line.”

Chapman was a late scratch from the Giants’ 6-4 loss to the D-backs on Wednesday night because he needed to undergo a physical to complete the deal, 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.

“I’ve already had people reach out to me saying that now that I’m here that they want to come here,” Chapman said. “I don’t think it’s going to be a hard sell. This organization is amazing. They do everything they can for their players. We have a lot of good players. I think we’re going to continue to build here. I think that people will see that from the outside.”