After rewatching it a few times, I see that Uggla bobbled the ball slightly as soon as it got to him. I think that made it impossible for him to get Espy at home, which he realized. So, his only chance is a 4-6-3 DP - even that would have been tough. The SS was moving to the bag and was in position for the turn. Suzuki made a smart move and stopped which Uggla may have seen in the corner of his eye. But I think after that first bobble, even if Uggla fired to SS, Tracy would have beat out the DP. The ball was not hit as hard as I thought watching it live and Tracy was motoring down the line.
Yeah, rewatching it here, it appears that because Uggla needed to bend and stretch out a bit to field the ball, he needed a second to get in position to check Espinosa. Your thought in that situation should ne that the runner will run on contact and you need to come home. It appears that Uggla may have been thinking that since the ball was hit back to him that the runner on 3rd may not go, because when he gets up it looks like he is thinking he is moving to look the runner back to 3rd so he can then get the out at first. He's not really positioned to go home, and instead, he looks toward 3rd and then his eyes catch Espinosa on his way home. At that point, he seems to then be caught between trying to readjust to throw home and then realizing he has to go with the alternative of a DP attempt. But he realizes he has no shot. Suzuki freezing is a distraction as well. Ultimately as soon as he doesn't come home and then the distraction makes the DP impossible, the play is over.
It appears to me that his thinking that he could check the runner back as opposed to assuming he had to come home was all a matter of a first instinct being incorrect, and then in a split second he knows its over. Davey had a good comment on that after the game. He's absolutely right. You don't really have the luxury of looking for a DP or an alternative play. You have to be thinking that you come home. There's a bobble and a double clutch there, but ultimately, the hesitation on what to do seems to be the root of the issue. The hit wasn't really right at him where he could keep the play in front of him. Once his eye comes off the runner, the instinct has to be to come up firing home, and he didn't.