WASHINGTON -- After the Mets dropped a 6-5 series finale to the Nationals on Sunday, manager Mickey Callaway lauded his team’s effort -- “What a series by our guys,” he said -- in defeat. For a club with real intentions to contend, these games mattered. The Mets’ three-run comeback on Sunday mattered. Even a walk-off loss could not do much to ruin their vibe.

After an offseason full of talk from new general manager Brodie Van Wagenen and company, the Mets finally had a chance to show off their new look. Here are three takeaways from New York’s first three games of the season:

1. The Mets’ identity has changed
Gone are the days of sitting back and waiting for a three-run home run. In their win on Saturday, the Mets scored 11 runs without a homer, shooting six of their seven RBI hits to the opposite field. The next day, New York used five singles -- three of them to center -- to construct a three-run game-tying rally.

New hitting coach Chili Davis preached situational hitting all spring. The Mets also brought in the right type of personnel to execute his message, from Pete Alonso to Robinson Cano.

The Mets are also a more athletic team, capable of improved defense and baserunning. In Sunday’s loss, Cano and J.D. Davis both made fine plays on the infield. Keon Broxton also received his first start of the year, finishing 2-for-2 with an infield hit and two stolen bases. This is no longer a station-to-station baseball team. Expect the Mets to run and catch better than they have in years.

2. The rotation isn’t perfect
Disclaimer: Jacob deGrom is excepted from all talk of imperfection. But Noah Syndergaard and Zack Wheeler allowed four runs apiece in their 2019 debuts, Steven Matz is coming off an uneven spring, and Jason Vargas, for all the trust the Mets still have in him, is coming off a year in which he posted a 5.77 ERA.

Beyond that, the Mets’ rotation depth consists of a mix of untested youngsters (one of whom, Walker Lockett, did not break camp with Triple-A Syracuse due to a minor shoulder injury) and veteran Hector Santiago.

To be clear, the Mets still boast one of baseball’s best rotations. So long as Syndergaard and Wheeler remain healthy, the staff should be just fine. But thoughts of pitchers steamrolling the competition with seven quality innings every night may be a touch premature. For those reasons, the Mets will continue to be linked to free-agent Dallas Keuchel for as long as he remains unsigned.

3. Pete Alonso is for real
Drawing definitive conclusions from 14 plate appearances may be a fool’s errand, but Alonso looked the part of a productive big leaguer in his first career series. Three of his six hits have gone for extra bases -- one to left, one to center and one to right. Alonso’s six total hits tied him with Keith Miller and Preston Wilson for the most by a Mets player in his first three career games.

“I’m really happy with the way I’ve been playing so far,” Alonso said.

Pitchers will inevitably adjust to Alonso, but the Mets have little doubt he can adjust back. One of the things Alonso carries with him on every trip is a composition notebook he uses to keep tabs on opposing pitchers. Alonso’s hitting abilities and intelligence appear to have staying power at the game’s highest level.