HOUSTON -- J.T. Realmuto’s 10th-inning home run that won Game 1 for the Phillies was either heart-stabbing or exhilarating, depending on which fan base’s viewpoint you were peering through.

There were plenty of other superlatives used to describe that game, too, including this one, which we hear plenty of times throughout the year, especially in the postseason:

It shifted the momentum firmly in the Phillies’ favor.

Momentum. That thing that makes teams, riding the high of winning one of the most important games they’ll ever play, feel like they have the advantage. Good times are rolling. They can’t wait to return the next day.

Except there’s this: The next night, the Astros teed off on Zack Wheeler, and Framber Valdez shoved. The Astros won, rather handily.

Where did the momentum go from there?

After a travel day and a rainout, the Phillies rolled over Lance McCullers Jr., who gave up five home runs in Game 3 and looked completely overmatched by Philadelphia’s lineup. And just like that -- poof! -- momentum shifted back over to the Phillies ...

... who were then no-hit by four Houston pitchers in Game 4.

You get the drift. Momentum is often talked about but rarely proven to be a thing. This year’s World Series may have just put this time-worn cliché to rest for good.

Except for one thing ... not everyone thinks it’s all phooey.

Houston manager Dusty Baker sure doesn’t. He believes, to a degree, that momentum can exist from game to game. It’s what a player does with it after recognizing it’s there that matters to him.

“If you have a strong mind, you can handle that shift,” Baker said. “But if you’re not strong mentally, then you’ll carry yesterday into today, especially if it was negative. So I just say to my guys, if it was negative, if they had negative results, ‘Leave it back there.’ And if you have positive results, take them with you and then try to pretend that really is momentum.”

“Pretend” -- interesting word choice. Is momentum something tangible that actually exists, or is it there purely to serve as either motivation when times are good, and comfort when things get tough?

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The biggest argument during the current World Series against momentum having any real, well, momentum, may have presented itself overnight between the final out of the Astros’ combined no-no in Game 4 and how the Phillies opened up Game 5.

Leadoff man Kyle Schwarber, who rather forcefully put the no-hitter behind him soon after the final out was recorded, telling reporters “I really don’t give a [expletive],” backed that up the next night, when he led off with a home run off Justin Verlander.

The Phillies didn’t win the game, but the homer tied the game at 1. From there, neither team grabbed control. The Astros stranded seven baserunners; the Phillies topped that with 12. Houston won the game by a run. Neither team gave any strong indication that a breakthrough was coming.

In other words, there was no Astros momentum shift after accomplishing something that almost never happens during the postseason -- no-hitting a lineup talented enough to have made it this far.

But again, managers -- specifically, the two working this World Series -- while not relying on the concept, don’t entirely push it aside.

Phillies manager Rob Thomson sees little validity to momentum being a thing that exists from game to game. But he does believe there’s something to in-game momentum.

Thomson noticed it in Game 1, when he turned to his biggest lefty weapon, José Alvarado, to replace Aaron Nola with one out in the fifth. Facing Verlander, the Phillies had clawed back from a 5-0 deficit to tie the game, and though it would mean the ‘pen would have to account for 5 2/3 innings (including the 10th), Thomson sensed at that instant, with Yordan Alvarez coming up, the game had shifted in their favor.

Thomson even used that word.

“I felt like we had gotten the momentum back in that game, and I didn’t want to lose it,” Thomson said.

The World Series moves back to Houston Saturday for Game 6 with the Astros leading, 3-2. If they win, perhaps there will be talk of momentum. There’s an argument that plenty was created by Chas McCormick and Trey Mancini’s spectacular defense in the end stages of Game 5.

Or, more realistically, a long day of travel will serve its purpose -- as a reset for both clubs.

“In baseball, especially with our team, from game to game, I don't think there's much momentum for our club,” Thomson said. “Because we've had some tough games, and come back the next day and played extremely well. I can't speak for anyone else's club -- but for our club, there is no momentum created from yesterday going into tomorrow's game.”