SANTA CLARA, Calif. -- The San Francisco 49ers are planning to keep coach Kyle Shanahan and general manager John Lynch around for a long time.

To that end, the Niners announced multiyear contract extensions for Shanahan and Lynch on Friday. The deals come on the heels of San Francisco's 30-12 win against the New York Giants on Thursday night that improved the Niners to 3-0 on the season, the team's second such start in the past four years.

Shanahan and Lynch arrived in San Francisco together in 2017, signing matching six-year contracts to take on their respective roles for the first time. After a down-to-the-studs rebuild the first couple of years, the Niners have become one of the league's most consistently successful teams.

Over the past four seasons, the Niners have appeared in a Super Bowl, been to two other NFC Championship Games and compiled 45 regular-season wins (tied for fourth-most in the NFL) and six playoff victories (second).

After going through three head coaches -- Jim Harbaugh, Jim Tomsula and Chip Kelly -- in as many seasons from 2014 to '16, Niners CEO Jed York sought stability at the top of the organization when he fired Kelly and general manager Trent Baalke after a 2-14 record in 2016.

York wanted to find a coach and a general manager who would be on the same page and still could challenge each other to get better. He tabbed Shanahan, then the Atlanta Falcons offensive coordinator, to be the coach and, after a series of interviews, surprised the NFL world by hiring Lynch away from the Fox broadcast booth to be his GM.

At the league meetings in March, York noted how pleased he has been with the work Lynch and Shanahan have done since arriving.

"Trust is earned and it's reestablished in any relationship that you have," York said then. "But that's what you need in order to be successful. You have to be able to make mistakes in order to get to a championship. I've been around folks where you're looking at every single draft decision that you make or every single trade that you make, and you're looking at it from an individual standpoint versus we've been in three NFC Championship Games and one Super Bowl in the last four years. That's a pretty good run. ... It's not ultimately where we want to be, but it's a pretty good run."

Before their new extensions, Lynch was signed through 2024 while Shanahan's contract took him through 2025. The team didn't release details of the latest extensions.