Arraez just keeps on rolling, huh? The dinger may have been a surprise but it's a pleasant one: if he can be a guy who hits 8-10 HRs along with 30+ doubles and a handful of triples he's going to be a much more complete player. He doesn't need a SLG% that's over .450 to be a terrific starting 2B, but he does need to keep it over .400 IMHO. A little extra pop on those occasional HRs helps a lot.
He's just become a really tough out. His BABiP is high, but not ludicrously so. The BB% is excellent for a guy who gets so many damn hits. he's doing a terrific job of controlling the strike zone: you can't strike him out often and you can't get him to chase much either. It's a really effective approach and he could be a terrific leadoff guy in the future.
I'm a little worried about Polanco right now. Maybe he's taking the slump at the plate out in the field with him? He's got to get those throws ironed out, because those free outs he's yielding can really haunt you. He probably needs a day or two off, and we've got the infielders up right now to do it, so hopefully Rocco gives him a day off and some infield instruction.