HOUSTON — Francisco Alvarez will appreciate Wednesday’s day of rest.

The Mets were planning on sitting their young catcher anyway on an afternoon game that followed a night game, but Alvarez getting nicked up on back-to-back games surely will make that decision easier.

Alvarez, who was pulled from Monday’s win after his right hand absorbed a foul ball, played Tuesday and had to be checked by trainers after scrambling back to second base in the eighth inning.

The rookie catcher, who had doubled in the inning, watched Mark Canha hit a sinking liner to right field, which Kyle Tucker caught with a sliding play.

Alvarez retreated back to second base and “rolled his knee a little bit,” manager Buck Showalter said.

“Felt fine,” said Showalter, who left Alvarez — who then hustled home on an RBI single from Eduardo Escobar — in the game. “We’ll see.”

Alvarez played Tuesday after undergoing X-rays a night prior on his throwing hand that came back clean.

He suffered the injury in Monday’s eighth inning, when Martin Maldonado fouled a pitch into Alvarez’s non-gloved hand.

Alvarez remained in the game initially before he was pulled in a blowout and went for X-rays.

“It’s hard to tell what’s swollen on him. His hands are very meaty,” Showalter said before the Mets lost to the Astros, 4-2, at Minute Maid Park. “Looks like we dodged one there, even though he didn’t.”

Omar Narvaez, who has become the backup, will start Wednesday’s matinee for his fourth game since returning from the injured list June 5.

The Mets are off Thursday, so the 21-year-old Alvarez will get a breather.

For scheduling, workload, injury and suspension reasons, Max Scherzer and Justin Verlander have been pitching in back-to-back games. Showalter has said since spring training he would prefer staggering his two co-aces.

“I’m still looking for ways to split those guys up,” Showalter said. “That’s going to be a challenge.”

In the second update of All-Star voting, the Mets had one position player who was set to qualify for the second phase of voting: Francisco Lindor.

The shortstop was second among National League shortstops, trailing the Braves’ Orlando Arcia and ahead of the Padres’ Xander Bogaerts.

The top two vote-getters at each position (and top six outfielders) will be announced Thursday and advance to the next phase of voting.

In Tuesday’s release, Pete Alonso was third among NL first basemen, narrowly trailing Atlanta’s Matt Olson; Alvarez fourth among catchers; Jeff McNeil seventh among second basemen; Brett Baty seventh among third basemen; and Brandon Nimmo 16th among outfielders.