BOSTON -- Angels left fielder Daniel Nava has played enough games at Fenway Park to know how easy it is for base hits down the right-field line to bounce into the stands and take away runs. So when he produced one in Friday's top of the ninth, with Mike Trout representing the tying run at first base and going on contact, his elation was tempered.
Nava knew there was at least a decent chance his line drive would be ruled a ground-rule double, which would keep Trout stationed at third base -- but he wishes he could've actually seen it play out.
"What stinks is that you'll never know, because that fan grabbed the ball," Nava said after the 5-4 loss it helped cause. "Whether it was in play, out of play, we won't know. And that's the part that's hard."
The Angels trailed by a run, with two outs, Trout on first and Red Sox closer Craig Kimbrel on the mound. Nava -- not long removed from his days as something of a cult hero in Boston -- pulled an 0-1, 98-mph fastball into the warning track in right field. It hit the dirt, struck the top of the five-foot fence beyond Pesky's Pole and caromed high.
Replay showed that it could've bounced back into the field of play. But a young fan in a Red Sox jersey stretched his right arm and caught it. And Trout, already rounding third base, was told to stay put.
C.J. Cron grounded out to end the game on the very next pitch, and the Red Sox knew they caught a break.
Kimbrel pointed at the fan, who helped him record his 17th save. David Ortiz, who earlier blasted his 522nd career home run, acknowledged the young boy by saying, "We played with 26 players tonight."
And Red Sox manager John Farrell admitted that his team might have "caught a break right there."
Mike Scioscia was fuming.
The Angels' longtime manager used his challenge, but replay officials ruled that the call stands. Scioscia was told there wasn't enough conclusive to rule fan interference, which could've allowed the Angels to tie the game. He called it "absolutely wrong" and said there's "no doubt" that it should've been overturned.
"I don't know what they're looking at in New York, but that ball is absolutely in the field of play when that fan touches it," Scioscia added. "Absolutely. It's a joke."
He acknowledged that the initial call was a tough one to make, but said: "The fan interference on replay is as clear as it's ever going to be. That's a brutal call for whoever is back in New York looking at it."
Trout had a couple of opportunities to be in scoring position for that play, on a fastball that squirted away from Red Sox catcher Christian Vazquez and an Albert Pujols fly ball that might have been deep enough to take a chance on. But he had no doubt he was going to score if Nava's ball would've eventually fallen in.
"The replays we all looked at looked like it was still in play," Trout said. "It's a tough one to end on."
The rule in question was 3.16, which states: When there is spectator interference with any thrown or batted ball, the ball shall be dead at the moment of interference and the umpire shall impose such penalties as in his opinion will nullify the act of interference.
"That's a hard play to overturn," he said. "Even if they overturn it, there's a lot of assumptions that go into it, so from my vantage point, it didn't look like they could overturn it."
But Mookie Betts, the right fielder who had a better view than anyone, was certain.
"We were joking that we were going to have to take [the fan] out to dinner because I think that ball was going to come back into play and obviously Trout is probably going to score on that ball, and it would have been another tough situation here," Betts said. "Fortunately, [the fan] has pretty good hand-eye coordination."
It helped secure the Red Sox's 43rd win, and it played a big part in handing the Angels their 10th loss in 11 tries, which dropped them 16 games below .500 and 19 1/2 out of first place.
"You have to let those things play out," Nava said. "Unfortunately when fans don't, it messes with the outcome of games. And right now we need every game."
Alden Gonzalez has covered the Angels for MLB.com since 2012. Follow him on Twitter and Facebook, and listen to his podcast. Ian Browne, who has covered the Red Sox for MLB.com since 2002, contributed to this report. This story was not subject to the approval of Major League Baseball or its clubs.