Moving forward, we at least learned something about Aaron Boone.

We discovered a new red line.

After the Yankees’ ugly, dispiriting, 8-3 loss to the Astros in American League Championship Series Game 4 on Thursday night at Yankee Stadium, a game that featured four pinstriped errors and zero Yankees hits in seven at-bats with runners in scoring position, Boone performed his version of a press-conference eruption.

Which, for him, didn’t mean emulating Dennis Green or Jim Mora or even Terry Collins. It meant acknowledging his players’ ineptitude and volunteering that he held a team meeting after the game, moves that are as out of character for him as monogamy was for Hugh Hefner.

“We played poorly tonight. There’s no other way to explain it,” Boone said early Friday morning. “And we need to flush this immediately because — we talked about it as a team, we need to get over this in a hurry and come put our best foot forward tomorrow.”

Some 16 hours later, Boone sat in that same seat, at the podium of the Yankees’ interview room, and expressed more interest in moving forward than in discussing his earlier mood.

“It’s obviously a lot on the line, and when we don’t play our best, I think everyone gets frustrated at that because we expect a lot of ourselves,” Boone said. “I know our guys expect a lot out of themselves.

“But one thing I know about them: When we have, throughout the year … had a clunker or not played well, I feel like this team, as much as any that I’ve been around, do a very good job of letting yesterday roll off and being hyper-focused on the day. And [I’m] confident that will be the case today.”

Boone has showed off his inner Savage only when arguing with umpires — typically inexperienced umpires — on behalf of his players. Otherwise, he acts as the master of cool, rarely betraying his emotions and exhibiting endless faith in his guys. For someone who was hired in part for his connectivity, he’s pretty good at disconnecting at his desired times.

It’s fair to wonder whether that unshakeability works against him at all this time of year. Whether it led to him not lifting Luis Severino and CC Sabathia sooner in last year’s AL Division Series and not giving up sooner on Adam Ottavino or Gary Sanchez this month.

Of course, such patience and rationality served Boone and the Yankees extremely well during the regular season, the results of which are likely to make him a finalist for AL Manager of the Year honors. And Boone has definitely managed this playoff run more aggressively than he did last year, most notably lifting starter James Paxton from ALCS Game 2 in the third inning despite the deficit being a reasonable 1-0.

Late Thursday night, after CC Sabathia walked off the mound for the final time with an ailing left shoulder, Boone’s predecessor, Joe Girardi, sat on the MLB Network set and grew very emotional as he paid tribute to his fallen ace. Girardi, for all the criticisms about him being detached from his players, wore his heart on his sleeve far more often than Boone did. And that personality trait definitely hurt Girardi at times, particularly when the team was in a funk and you could feel his tension from a borough away.

Of course, in Girardi’s final season running the Yankees, he took the team within a win of the World Series. Boone, after not reaching the ALCS in his rookie campaign, was trying to get two wins away from the World Series in Friday night’s Game 5.

The truth is that Boone, in his second year managing at any level, is still evolving. Obviously he has earned the right to return for a third season. It’ll be interesting to see how he further evolves and to keep our eyes open for those rare red lines.