Transcript for Fan interference gives Red Sox key win
But this is not exactly a priceless moment if you're an Astros fan as I stare at you. Trying to make me cry. Some worry this could cost the 'stros a trip to the world series. Fans reaching for the ball. A possible home run ruined. Gio Benitez is here with that story. Good morning, gio. Reporter: Good morning. Yeah, this is sparking some nationwide outrage right now but the fan is now speaking out saying he did nothing wrong, so many this morning playing back that tape in slow motion. Reporter: This morning controversy surrounding the play during the astros/red sox ALCS match-up leaving some wondering was Boston given an unfair advantage? In the first inning Jose altuve hit what looked to be a two-run home run over the right field wall. As it landed umpires ruling that the fan prevented red sox outfielder mookie BETTs from making a play on the ball. But the question remained, did the fan interfere? Did they reach over that yellow line into the field of play or is mookie over the field of play? Reporter: The MLB says this about fan interference. When a fan clearly prevents a fielder from catching a fly ball, the umpire shall declare the batter out. He gets stopped from catching it from the hand of the fan. Reporter: The ruling taking two key runs off the scoreboard for the Astros. Reached my hand up. I felt like somebody was kind of pushing my glove, you know, out of the way and I got to see a little bit of the replay. I guess he got the call right. There's no mechanism for me to change their mind, change their interpretation or the fact that I thought it was a row or two into the stands. It doesn't matter what I think. Reporter: The red sox went on to win 8-6. The final score taking a 3-1 lead in the best of seven series. This isn't the first time an action by a fan has changed the outcome of a conference series game. In 2003 at Wrigley field Steve Bartman was launched into infamy when he reached for this ball during the cubs/marlins playoff game. His reach disrupted a potential catch by the cubs. The marlins wound up winning the game and the series. When the cubs finally broke their world series curse in 2016, Bartman received a world series ring. It's not known yet if such a ring is in the future for Troy Caldwell, the fan many are now blaming for the interference call. Caldwell maintains he didn't cross the home run line. He was mobbed as he left the stadium. Nothing to talk about. Reporter: Yeah, listen, when word got out Caldwell was worried that he'd need a security escort after the game, a local barbecue spot in Houston tweeted during the game that he was just being a fan and told people around him at the game to buy him a beer and they offered him some free barbecue. Get a whole mob down at the barbecue joint. An ulterior motive for offering that? Thank you, gio.
This transcript has been automatically generated and may not be 100% accurate.