I wish I could help you. I have both also and Beltre is pissing me off!!! I think Blalock could be in for a big year, but I'm not happy with the Rangers management. They've sat him 3 times already, which is ridiculous. He hit Zito well, so keep starting him, right? Anyways, Beltre is killing me at his -1 total this week.
I'm going to start Blalock from now on just because he will hit either in the 6th spot or the 2nd spot, which should be most of the time, and Beltre is going to have to show me something from here on out.
A sidenote, I think the whole Blalock at 2nd base thing during the spring wasn't for the Rangers. I believe they have every intention of trading him at some point this year, and playing him at 2nd makes him more marketable. IF Teixeira ever starts hitting like everyone thinks he can, I would seriously look at Blalock being traded, as part of a package, to the Royals for Beltran. Sound crazy? Beltran is a very very good friend of ARod, who has been lobbying Tom Hicks hard to get him. The Rangers have learned how much a very good CF can mean to their team. So, Relaford would be moved out and Blalock would be the 2nd baseman. He's cheap and he will be a stud when they have their team built up again.