Francisco Alvarez must be on Mets' playoff roster

During Sunday's game against the Braves in Atlanta, you could see that 20-year-old Mets rookie Francisco Alvarez was starting to get comfortable at the plate.

In the fifth inning against Dylan Lee, Alvarez fell into an 0-2 hole before working an eight-pitch at-bat where he just missed a fastball (fouling it back) before eventually striking out on the eighth pitch on a nasty slider.

More important than the outcome of that at-bat was how Alvarez looked during it. As he was up there, he had a bit of a smirk on his face. He was nodding his head. He looked like someone who was starting to relax after making his big league debut two days prior. He looked like a dangerous hitter who was ready to break out.

On Tuesday night against the Washington Nationals at Citi Field, that breakout happened. 

After the Mets were officially eliminated from NL East contention in the middle of the game, Alvarez replaced James McCann at catcher. And in his next two at-bats, he showed everyone why the Mets called him up.

In his first at-bat, Alvarez smoked a 2-2 curve from Carl Edwards, Jr. over the fence in left-center. The ball traveled 439 feet and had an exit velocity around 108 mph.

In his second and final at-bat, Alvarez ripped a double to left field that bounced off the wall. Like his homer, the double had an exit velocity around 108 mph.

As Alvarez was punishing baseballs, McCann -- who has been one of the least productive position players in baseball this season -- was taking another 0-for-4. McCann has one hit in his last 27 at-bats and is hitting .182/.246/.253 in 60 games this season.

What became clear on Tuesday, with the juxtaposition between Alvarez and McCann front and center, was that the Mets absolutely need to carry Alvarez on their postseason roster when they open the Wild Card Series against the San Diego Padres on Friday at Citi Field.

We'll go over who Alvarez should replace and the catching aspect of it in a little, but first, here are some numbers to chew on...

The first is that since 2015, only seven players under the age of 21 have had a game with at least one home run and one double (hat-tip to Matthew Brownstein for the stat).

The players?

Carlos Correa, Ronald Acuna, Jr., Juan Soto, Vladimir Guerrero, Jr., Fernando Tatis, Jr., Wander Franco, and Francisco Alvarez.

The second is that Alvarez joined a list of just six players since 1990 to catch a game in the majors before turning 21 years old -- a list that includes Ivan Rodriguez, Joe Mauer, and former Met Todd Hundley (hat-tip to SNY contributor Jacob Resnick for the stat).

Now, Alvarez smoking two baseballs on Tuesday after going hitless in his first eight big league at-bats doesn't mean he'll be a force in the playoffs. But it's quite clear that he has a chance to be a difference-maker if he can keep things slowed down and harness his power.

And with the Mets' most glaring need being right-handed power at DH and off the bench, it would be lunacy for the Mets to not carry Alvarez on the roster, where he can DH against Padres lefty Blake Snell whenever he pitches, be a big bat off the bench, and perhaps get some at-bats against righties -- depending on how Daniel Vogelbach plays.

In order to fit Alvarez on the roster, the Mets likely have two options.

The first would be carrying Alvarez over Mark Vientos, whose presence on the roster would be a bit redundant if Alvarez is on it. That would give the Mets three catchers.

The second would be carrying Alvarez as the second catcher over McCann and keeping Vientos.

The idea there would be to start Tomas Nido behind the plate every game and have Alvarez available to catch in an emergency. But the easier and cleaner plan is probably having Alvarez on the roster and Vientos off.

Is there a scenario where the Mets decide they're willing to trust Alvarez to catch in the postseason? Perhaps. But it's hard to envision. And it would be a hell of a lot to put on the shoulders of a 20-year-old just a few games into his major league career.

But regardless of Alvarez's age, it's clear that his bat plays right now. And the Mets, whose quest toward a World Series title is about to begin, need Alvarez to be a part of it.