The left side of that infield is way overpaid, and on top of that, is downright bad. Guzman got paid on the basis of his 2001 first half, which convinced everyone that he has an untapped upside. Worse, Castilla's 2004 Coors split is substantial:
Castilla - AVG OBP SLG
Coors - .321 .379 .575
Elsewhere - .218 .281 .493
The Ex-Spos just paid over $20 million for six combined seasons of those two guys? Ouch.