Here's what Pete said about using Ellison in the 6th when I asked him.
"There’s a lot of game left. You’re talking about the sixth inning. I don’t want to use my better pinch hitters in my estimation that early in the ball game, especially with two outs. It’s tough to come up with a two-out hit. If Jason comes up with a two-out hit, that’s a bonus. To me, that’s too early to use my best. Especially since they have (Pedro) Feliciano, they’ve got (Scott) Schoeneweis, another kid (Willie Collazo) and their closer (Billy Wagner) is left-handed. So I might have needed all three of them to win a game."