I don't think the Astros are willing to finish out the year with Valbuena as their starting third baseman. He's been fine in the field, and for a while his incredibly odd bating stats were good enough. While he still leads the team in HRs, he hasn't hit one in more than a month. Meanwhile his average remains below .200 and he has an equally atrocious OBP. Lowry represents and immediate offensive upgrade at 3B at no cost to the Astros. I think the Astros will add another pitcher and maybe a low rent corner outfielder to hold down Springer's spot until the end of August. They'll use their deep farm system, not major leaguers, to make those deals. So that's what you do with an accumulation of prospects. Exactly, which is why they won't be trading a major leaguer like Jed Lowrie per the OP. That doesn't mean that Jed Lowrie wouldn't be a good fit with the Cubs. Just that I seriously doubt he's available.