The Angels want to add a starter. It’s more likely that they don’t have the chips to acquire a premium one, but they’re doing their due diligence anyway.

This week could be a big one with regards to that pursuit.

This is the week when the erratic Ervin Santana will make two tough starts (against the Tigers on Monday and against the Rangers on Saturday), this is the week more will be known about the health of Dan Haren (he’ll make a rehab outing today, and if all goes well, he could start against Texas on Sunday), and this may be the week that dictates how aggressive Jerry Dipoto is in his pursuit of another rotation arm.

We’re now 15 days away from the July 31 non-waiver Trade Deadline. And the more time passes, the less likely it seems that the Angels can acquire a guy like Zack Greinke or Cole Hamels.

First, there’s the fact each of their teams would like to resign them. The Phillies, Paul Hagen writes, are entering a critical stage with Hamels. The Brewers, according to Adam McCalvy, pushed back the struggling Greinke to give him a blow (making him less appealing on the trade market and more likely to be retained, perhaps?).

Second, there’s the whole “assets” thing. The Angels don’t have a lot of that to give up. As one executive said, if they’re going up against the Rangers for a starter (T.R. Sullivan says Roy Oswalt’s effectiveness could determine how aggressive they get) it would be “like taking a butter knife to a gunfight.” The only heavy artillery the Angels carry is Peter Bourjos, the high-upside center fielder who’s without an everyday role but is a big part of their long-term plans. Dipoto has continued to stress that the Angels will not trade Bourjos, but things can certainly change. The only way I see them giving him up is if it’s for a starting pitcher they can resign — not one who’s going to walk away in two months and leave them with nothing.

And that brings me to the third reason — the new CBA. The extra Wild Card has put more teams in the race for the playoffs, making less of them sellers in July. But a bigger reason for a possibly slow market could be that the only players who bring back Draft pick compensation upon signing with another club are those who spent the previous full season with the same team. For example, if a team trades for Hamels and he signs elsewhere, that team gets no additional Draft picks in 2013. If he stays with the Phillies and he signs elsewhere, the Phils do get the compensation. One scout said the trade market so far is “extra quiet” and “not much is happening” yet. No surprise there.

Of course, there are other, more-attainable starters out there (Wandy Rodriguez and Ryan Dempster come to mind). Will the Angels go outside of themselves to add another front-line guy?

It may depend on how this week goes.

– Alden Gonzalez