T.J. Rivera hit a two run homer in the bottom of the fourth to bring the Mets with three runs. The game was now in play after Noah Syndergaard had allowed five runs in 3.2 innings. 

The home run changed the dynamics of how Terry Collins needed to use his bullpen. 

Now, even with the expanded rosters, the Mets bullpen was a bit overworked. The Mets needed their bullpen to pitch 11.1 innings over the previous two games.  With Syndergaard getting knocked out in the fourth, the bullpen would need to get another 5.1 innings. 

Sean Gilmartin pitched the first 1.1 innings. His turn in the lineup would come up in the sixth, and Collins would do the right thing in pinch hitting Kelly Johnson for him, especially with a runner in scoring position. 
At this point, Collins had to figure out where to go for the final four innings. Collins went to Josh Edgin. Now, Edgin has pitched in the previous two nights (even if the one outing was just to face one batter). It is also important to note this is his first season back from Tommy John surgery. 

More important than any of that, Edgin has made 10 appearances this year pitching to a 6.00 ERA and a 1.500 WHIP. Righties are hitting .273/.467/.545 off him this year and .243/.344/.346 for his career. He’s a LOOGY and not a cross-over lefty. None of this stopped Collins for sending him out for a second inning. 

On Edgin’s 30th pitch, he walked Jace Peterson to load the bases. Hansel Robles came in and couldn’t get out of the jam.  He allowed a two RBI single to Dansby Swanson to make it 7-2 putting the game reasonably out if reach.  This was a situation created by Collins, and Robles couldn’t bail him out. 

Now, there will be some who will defend Collins pointing out Freddie Freeman and Nick Markakis were due up the following inning. It’s a valid yet misguided point. 

Yes, you want Edgin facing Freeman and Markakis. However, you don’t want Edgin having them after having pitched in the prior inning and with Edgin pitching on the third consecutive game. It doesn’t make sense. 

It was incumbent on Collins to look ahead and use a different pitcher in the sixth and leave Edgin in reserve for when Freeman and Markakis came to bat. Collins tried to get two innings out of Edgin.  It was a move that backfired, and it helped the Braves blow the game open.