1) Andy Pettitte's ability to throw strike 1.
The Angels showed a great approach against Burnett by taking what he gave them and not being afraid to swing at early strikes. Andy can't fall into the same trap of lobbing one over the plate just to throw a strike, but he also can't be passive and try to pick corners because pitching from behind in the count will get you into trouble against the Angel lineup.
2) Yankees ability to work counts against Saunders and get to the Angels' bullpen as early as possible.
Angels' starters, with the exception of Scott Kazmir, have been relatively effective in neutralizing the Yankee offense in this series, but have not been able to work into the 7th and 8th innings. The Yankees stand a much better chance of winning if they can knock Saunders out in the 5th or 6th and get to the soft underbelly of the Angel's pen.
3) Hitting with runners in scoring position.
Neither team has done it very well at all this series. The Yankees had a flash of it in the 7th inning of Game 5 but then couldn't get it done in the 9th. With the weather sure to have an effect on hitting and running the bases, getting a clutch hit or two could make the difference.
4) Which team runs the bases better.
See comments above. With scoring opportunities potentially being at a premium tonight, a stolen base one way or a misguided attempt to take an extra base the other way could have a huge factor in a close game.
5) Which manager will blink first.
For all the talk of how he's the best in the business, Mike Scioscia hasn't exactly written the book on how to win a series with his decision-making so far this series. But Joe Girardi has been more than up to the task of matching Scioscia's bad calls step for step. If the game is close in the late innings, the manager who makes the first bad bullpen call or questionable pinch hitting or pinch running change could end up losing it for his team.