WASHINGTON -- Pete Alonso shifted the bat subtly, grabbing the barrel with his right hand so that he could use its weight to his advantage. He flicked his wrist, twirling the bat like a drum major before letting it fly freely into the air. It made two more rotations on its path to the ground.

“That’s called a bat flip,” Alonso said afterward, as if any doubt existed as to the action or its implications. The Mets had spent the first half of their series at Nationals Park taking baseball after baseball to various parts of their faces, backs and shoulders. They were upset, if not downright angry. They also knew that winning the series -- perhaps even with a bit of flair -- would represent far more effective retaliation than engineering a beanball war.

So when Alonso clouted his first career grand slam in the fifth inning on Saturday, putting the Mets in position to win a 5-0 game over the Nationals and ensure a series victory, he let his bat’s flight do the talking. If bat flips are a language unto themselves -- sometimes they express rage, sometimes whimsy, sometimes joy -- then Alonso is capable of speaking it with fluency. His flip expressed a certain cool assurance.

“He had it coming,” manager Buck Showalter said.

Less than 48 hours earlier, it was Alonso who had hit the dirt in the ninth inning on Opening Day, when a Mason Thompson fastball split his lip and left him swollen and bloodied. The Mets simmered after that one. When Francisco Lindor suffered a similar fate the following night, they momentarily lost their cool, with Showalter leading the charge out of their dugout.

Then on Saturday, Alonso pulled a Joan Adon fastball high into the air, where it battled the wind for nearly seven full seconds before finally settling over the left-field fence. The resulting four runs made a winner of Chris Bassitt, who fired six shutout innings in his Mets debut, while allowing Showalter to become the first manager in Mets history to win his first three games with the club.

“Oh, it feels nice,” Alonso said, summing things up for all of them. “Grannies are sick.”

Sicker still are grannies that exorcize ill will. Although few in the Mets clubhouse believed the pitches that hit Alonso and Lindor were intentional, they also figured that was missing the point. If the young Nationals could not control their high-velocity fastballs, Showalter and others reasoned, then they shouldn’t have been throwing them anywhere near the inner edge of the plate. Even when Adon struck Starling Marte with a breaking ball on Saturday, Showalter noted: “It’s not intentional. But it still doesn’t make you happy.”

Alonso was not happy on Thursday. Lindor was not happy on Friday. So they set about doing something to change their mood, grinding out at-bats early against Adon. As the Mets drove up the rookie’s pitch count, Adon lost effectiveness, allowing a leadoff single, two walks and a wild pitch in the fifth. That brought up Alonso, who jumped on a 2-1 fastball and drove it high into the air in left. Despite a stiff breeze threatening to knock down the ball, Alonso contributed just enough muscle to power it 358 feet over the fence.

Then he flipped his bat, in what he called an unscripted moment. As he rounded the bases, Alonso pressed his finger to his lips -- a signal, he said, for both the Nationals’ dugout and their fans to shush.

“It’s something that just has to happen organically,” Alonso said of his celebration.

Within that moment was the type of joy that Alonso has always demonstrated since making the big leagues -- the type that Showalter described as “a guy that walks in here every day like he’s playing his first game in Little League.” This time, Alonso’s happiness may have been tinged with some harsher emotion, as well, given the events of the preceding two days. But his grand slam stood as a monument to what the Mets hope will be the identity of this team. Alonso felt it was important to return to the lineup on Friday, one day after spitting out blood on the field. Lindor felt the same.

For Alonso to accomplish what he did amidst those circumstances was not lost among his teammates.

“We’ve got two guys with completely busted mouths already two games in, and they’re in the lineup the next day,” Bassitt said. “To be on a team that wants to grind as much as this team? Good luck. We’re just going to grind you until you break.”