How little-known MLB ‘fourth out’ rule led to this Red Sox run you have to see to believe

As one of the hottest teams in baseball over the last month and inching toward the postseason, the Red Sox rolled into Rogers Centre on Monday night to take on the Blue Jays.

In the end, Boston was handed its third-straight loss, a 2-1 defeat despite a solid six-inning performance from Sonny Gray on the mound. The Red Sox nearly pulled off a late comeback, though — and one of MLB's strangest rules led to the team's lone run.

In the top of the seventh, players, teams and broadcasters were all left a bit confused as a "fourth out" rule came into play. 

Here's a look at the wacky run the Red Sox scored vs. the Blue Jays, why it counted and more. 

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How rare MLB ‘fourth out’ rule led to Red Sox run

A series of two plays in the top of the seventh sparked the confusion in Boston vs. Toronto. First, with nobody out and runners on first and second, Nick Sogard hit a line drive to Vladimir Guerrero Jr. at first base. Because the ball hit the ground, Guerrero threw to second base for a force out; Sogard reached first, while Anthony Seigler advanced to third on the play.

That play appeared to cause some initial confusion. The scoreboard at Rogers Centre counted it as a double play despite it only resulting in the first out of the inning — and the players on the field appeared to also think there were two outs afterward.

On the following play, Ceddanne Rafaela flew out to center field, the second out of the inning. But because the baserunners thought there were two outs already, they were sprinting around the bases without tagging up, thinking the inning was then over.

Eventually, however, the Blue Jays got the ball to first base, where Sogard was called out for failing to tag up. What then resulted in so much confusion was that the other Red Sox base runner, Seigler, ran all the way home before Sogard was out at first.

Meetings began with the umpires and managers, with players also getting involved; the question was whether Seigler's run should count.

With the added confusion of baserunners and fielders having the incorrect amount of outs, eventually, crew chief Chris Guccione explained why Boston's run would count despite Seigler not tagging up.

“What we have here is we have a time play,” Guccione said, “Meaning when the third out was made at first base with the runner not tagging up, the runner that was on third base also did not tag but crossed home plate before the third out was made at first base. So we're going to New York to do a rules check."

"After calling New York and getting it all straightened out, the run is going to score. End of the inning. Two runs for Toronto, one run for Boston."

The "time play" aspect of the play is what ultimately allowed the Red Sox to get on the board. Essentially, MLB has a rule that states that when an appeal play takes place on an inning-ending play, such as Sogard being thrown out at first base, “the appeal play decision takes precedence in determining the out."

Guccione explained postgame that with Sogard's out at first base being a "time play," rather than a force play, because Seigler crossed home plate prior to Sogard being out, his run counted.

“Both Boston runners, thinking there were two outs, just took off,” Guccione told a pool reporter following the game, per MLB.com. “When the second out was made, now we have two runners who have failed to return and tag up correctly. At that time, the guy from third had crossed home plate and the guy who was at first was standing at second. Toronto knew he hadn’t tagged up and threw to first base to make the third out. Well, that’s a time play, meaning it’s not a force play. If it’s a force play, the run does not score automatically. If it’s a time play — meaning, ‘Was the out made before or after the runner crossed home plate?’ — in this case, the runner crossed before the appeal play was made [at first]. In this play, it’s what you call an apparent fourth out.”

Additionally, because Toronto's fielders had left the field of play — which is considered past the third-base line, walking to the dugout — the team was unable to appeal to third base, which would have been necessary to prevent the Boston runner from scoring.

"It didn't cross my mind until I walked into the dugout, remembering that the timing play exists," third baseman Charles McAdoo said postgame, per MLB.com. "And that was a situation where it came into play. And right when I walked in the dugout, I was like, 'Darn it, I missed it.'"

Both managers addressed the play postgame; Chad Tracy called it a "very weird situation," while John Schneider disagreed with the umpires' decision about the third-base appeal.

“They told me that all of my players were across the third-base line before [home-plate umpire] Charlie [Ramos] waves off the run, which I 100% disagree with. I don’t know if Vlad is that fast after he got the ball at first," Schneider said, per MLB.com. "We weren’t given the opportunity to appeal to third. Going forward, when that play happens again in the next 100 years, if it’s us, we will record the lead out at third. That’s the best I got.”

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What is MLB's fourth out rule?

MLB's "fourth out rule" is Rule 5.09(c)(4), which states that when an appeal play takes place on an inning-ending play, “the appeal play decision takes precedence in determining the out.”

"Appeal plays may require an umpire to recognize an apparent 'fourth out,'" the rule states. "If the third out is made during a play in which an appeal play is sustained on another runner, the appeal play decision takes precedence in determining the out. If there is more than one appeal during a play that ends a half-inning, the defense may elect to take the out that gives it the advantage. For the purpose of this rule, the defensive team has 'left the field' when the pitcher and all infielders have left fair territory on their way to the bench or Clubhouse.'"

NESN's broadcast of Monday's game also helped explain the "fourth out rule."

Per MLB.com, past instances of the rule being taken into consideration include a Pirates vs. Nationals game in June 2022 and a Dodgers vs. Diamondbacks game in April 2009.

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