It pretty simple when you think about it. Yost wanted Bush to pitch in the bottom of the seventh, so had him bat in the top of the inning. Bush gets a hit, he's on first, and he's still probably going to pitch in the bottom of the inning. Once Bush had to run from first to third he was winded, so Linebrink comes in. You can say in hingsight "he should have used a pinch runner", but if the pinch runner had been stranded at first Yost would be criticized for wasting a pinch runner and going to our crappy pen too early. I'd love it if we could get a manager that could tell the future. If Yost is fired and this next guy can't tell the future are you guys going to tear him to shreds too?