Having seen Castillo go to second base without going back to touch first base, McCann threw to first, mistakenly believing that once the infield fly rule was called, the baserunners had to treat it like a normal fly-ball situation.
Both runners stayed close to their respective bases before Jones dropped the ball.
"I knew that he didn't tag, and I thought with the infield fly, it was a caught ball," McCann said. "When I saw [Castillo] run, I thought that he had to at least tag. I didn't know the whole rule."
Further complicating matters, first baseman Eric Hinske actually tagged Reyes, who was automatically out because of the infield fly rule. As Hinske was making the tag and looking for a call, Pagan raced from third base to a plate that had been left unprotected by McCann, who was standing on the first-base side of the mound.
"Trying to tag a guy out who was already out, you don't have to know the rule that they run at their own risk," said a befuddled Braves manager Bobby Cox.
Pagan said that he was initially going to run toward the plate even before McCann made the throw to first base, but third-base coach Chip Hale held him until the throw was made.
"I wanted to go right away," Pagan said, "but Chip was holding me, and that was good. He made the right decision. I don't know. I guess [McCann] didn't hear the call or didn't know the situation. So we took advantage of it. It was a big run for us."
Pagan's run gave the Mets a two-run lead and accounted for the first of the two insurance runs they plated during a seventh inning that Jones, McCann, Hinske and the Braves would like to soon forget.
"That infield fly, I looked over at [shortstop] Omar [Infante] thinking it was at shortstop," Jones said. "I looked back up, and it was in between the pitcher's mound and the infield cut. So, late break. I don't really know what happened after the drop. It was chaos. [McCann] thought the play was dead once they advanced. I don't know why he threw to first. That screwed everybody up when he threw to first. Then I saw Pagan break for home, and it was just too late."