WASHINGTON — A couple of injuries and Francisco Alvarez’s sky-high potential prompted the win-now Mets to let the young catcher learn on the job. 

There are times his talent will overwhelm.

There are times his age will shine through, and he will look overwhelmed. 

Both occurred Monday, when Alvarez had a solid day at the plate and a dreadful moment on the base paths in a 10-3 loss at Nationals Park. 

On a day the offense struggled to find the big hit, Alvarez reached base in three of his four plate appearances.

He knocked a bloop to left field that he hustled into a double and worked the only two Mets walks of the game. 

But he and the Mets were burned by a rookie mistake after his first walk. 

Alvarez was on first in the second inning with the bases loaded and two outs in a 1-1 game.

With Brandon Nimmo at the plate, Nationals catcher Keibert Ruiz threw behind Alvarez and picked him off to end the second inning, taking the bat out of Nimmo’s hands. 

“Since it was a lefty hitting, I couldn’t see when the catcher moved over,” Alvarez said through interpreter Alan Suriel. “Once I was trying to get back, it was too late.” 

Alvarez acknowledged he was too far off the base and said he would learn from the slip. 

“It’s obviously not ideal,” said Nimmo, whose at-bat against Patrick Corbin had one ball and one strike. “He’s going to be just fine. He’s a young kid in the MLB, and he just wants to help. I’d rather tame a lion, and he definitely is [a lion].” 

Alvarez, who is receiving everyday playing time because of injuries to Omar Narvaez and Tomas Nido, also was charged with an error in the game, although he wasn’t completely to blame.

His fourth-inning throw to second attempting to throw out a stealing CJ Abrams bounced before it reached Jeff McNeil, who couldn’t come up with the short hop that enabled Dominic Smith to then score from third base. 

Manager Buck Showalter praised the 21-year-old after his 29th career major league game and said he “did some great things,” too. 

Alvarez drew walks.

He ran hard all the way on a flare to left fielder Stone Garrett, who couldn’t secure the catch and then was too slow to the ball to throw out Alvarez at second. 

On a team with light-hitting catchers, Alvarez has easily been the best option at the plate and upped his OPS to .694. His glove, too, has been better than advertised. 

But 21-year-olds sometimes will play like 21-year-olds. 

“I like the kid a lot,” Showalter said. “The biggest thing is I don’t think it’ll happen again.”