NEW YORK -- For everything the Mets had accomplished this offseason -- swinging a blockbuster trade, signing free agent after free agent, churning over roughly half their roster -- the team entered Spring Training feeling incomplete. There were still moves to be made, depth to be found. And so even after arriving in Port St. Lucie, Fla., Mets officials continued working.

Days after pitchers and catchers reported to camp, the Mets made a significant addition to fill out that group, signing Taijuan Walker to a two-year contract with a player option for 2023. The agreement includes $20 million guaranteed, according to multiple sources, and adds an established starting pitcher to a rotation that, on paper, already ranked among the better groups in the league.

“You talk about talent plus experience,” manager Luis Rojas said. “We’ve heard about some leadership in there as well. So I think it can be a great addition.”

Walker, 28, posted a 2.70 ERA over 11 starts last season after returning from Tommy John surgery late the previous year. Fully healthy, Walker struck out 50 batters over 53 1/3 innings split between the Mariners and Blue Jays. He is a former first-round Draft pick who owns a 3.84 career ERA over eight years in Seattle, Arizona and Toronto, though he’s never quite completed a full big league season. The closest Walker came was in 2015, when he started 29 games and threw 169 2/3 innings.

In New York, that should be enough. Walker figures to slot into the rotation after Jacob deGrom, Carlos Carrasco and Marcus Stroman, bumping either David Peterson or Joey Lucchesi out of that mix. Such depth should prove important for the Mets coming off a 60-game season, with innings limits potentially in play for Peterson or others. Earlier this week, Rojas said the Mets will consider various ways to combat that issue, potentially including using openers and other strategies.

“We still haven’t committed to a plan there,” Rojas said. “We like our depth there. Right now, we have some names there that we’re looking forward to seeing in action. … Yes, they did have a shorter season, but once we get to a point of ramping up and getting into the regular season, I know [we’re] going to start talking about what’s happening and how the season’s developing.”

Walker’s two-year deal also gives the Mets insurance past this season, with both Noah Syndergaard -- who is due back from his own Tommy John surgery around June -- and Stroman eligible to become free agents.

More than anything, Walker offers the Mets another legitimate rotation arm, pushing everyone else down the depth chart. In recent years, the team struggled to find rotation consistency, relying on inexperienced players such as Corey Oswalt, Walker Lockett, Ariel Jurado, Wilmer Font and others to start in a pinch. Last season alone, the Mets used 10 starters over 60 games, including Seth Lugo and Robert Gsellman, whom they attempted to stretch out on the fly due to a lack of other options.

Now, the Mets have plenty. In addition to their top six starters and Syndergaard, the Mets brought aboard Jordan Yamamoto, Jerad Eickhoff, Sean Reid-Foley and others to provide depth. Most if not all those pitchers will start the year in the Minors, giving the Mets one of the strongest and most experienced Triple-A rotations in baseball.

“Before getting traded, I knew they were a really good pitching team,” Lucchesi said. “I just heard from friends that they’re super professional.”

While the Mets will never say they’re done shopping -- “I definitely subscribe to the ‘never can have too much pitching cliché,” general manager Zack Scott said recently -- they have created a roster without clear holes. Since November, the Mets have agreed to terms with 10 free agents on big league deals, completed seven trades and signed nearly two dozen others to Minor League pacts. They’ve turned over nearly half their 40-man roster, putting actions behind their words that it’s a new era in Flushing.

“Just tremendous,” Rojas said. “You talk about depth, and depth in every aspect of the game, whether it’s starting pitching, whether it’s bullpen or the position players, it’s always a luxury. A guy like [Walker], he just makes your rotation so strong when you can add him.”