HOUSTON -- The Red Sox are a dangerous team when they're able to grab a lead first, which they did in Game 4 thanks to a two-run first inning. But it looked like the Astros had a chance to erase that early lead when Jose Altuve hit what potentially could have been a two-run home run in the bottom half of the inning. 

However, the play was ruled fan interference by right field umpire Joe West, who determined that Mookie Betts was obstructed as he went airborne to make the catch at the wall. Have a look for yourself:

"When he jumped up to reach for the ball, the spectator reached out of the stands and hit him over the playing field and closed his glove," West said to a pool reporter following Game 4, a thrilling 8-6 Red Sox victory, giving Boston a 3-1 advantage in the ALCS. "He hit the ball to right field. He jumped up to try to make a catch. The man interfered with him over the playing field. That's why it's called spectator interference."

The play was reviewed by the umpires -- it was a crew chief review, not an Astros challenge -- and it was determined the call on the field "stands." Officially, that means MLB did not see enough evidence to overturn West's call.

MLB rule 3.16 covers spectator interference. Here is the relevant text, emphasis mine:

In every case of spectator interference with a batted or thrown ball, the ball shall be declared dead and the baserunners can be placed where the umpire determines they would have been without the interference. When a spectator clearly prevents a fielder from catching a fly ball by reaching onto the field of play, the batter shall be ruled out. But no interference is called if a spectator comes in contact with a batted or thrown ball without reaching onto the field of play -- even if a fielder might have caught the ball had the spectator not been there. 

As noted, the replay crew in New York could not determine whether the fans in right field did actually reach into the field of play to interfere with Betts and prevent him from making the catch. Is that debatable? Absolutely. Given the evidence, it seems to me whatever was called on the field was going to stand, and in this case West called fan interference.

"He just said that there was fan interference on the field, and my argument was more about the fact that the ball was leaving the yard, the trajectory was there," said Astros manager A.J. Hinch to Lauren Shehadi of TBS during an in-game interview. "Jose paid kind of the ultimate price for something out of his control. I'm not sure if Mookie makes that catch, he's a great athlete, but how it's an assumed out is unbelievable."  

The potential game-tying homer was erased, Altuve was called out, George Springer was sent back to first base, and the Red Sox were ultimately able to escape the first frame without surrendering a run.

Troy Caldwell, the fan in the orange polo, joked he will "need security to escort me out of here if the Astros don't come back to win this."

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