The thing to remember at times like this is that we knew this wasn't a very good team going into the season. Bad teams have losing streaks, and we have to keep them in perspective before we gnash our teeth down to the pulp. This team isn't as good as the one that started 11-7, and neither are they as bad as they're playing now.
That said... Livan Hernandez is (now, at least) a terrible pitcher who never met a leadoff hitter he didn't try to put on, and the Pirates couldn't do much of anything against him. The Bucs did manage five walks and eleven hits, but before the ninth inning, only two hits, both doubles, went for extra bases. With a couple more well-placed hits, the Bucs might have scored six or seven runs instead of four, but the big problem going forward isn't clutch hitting or anything like that, it's the lack of power.
Ian Snell looked pretty good through the first few innings, and the good news here is that his fastball is back, topping out at 96 or so. He had a rough time in the fourth, but finished the afternoon with a quality start. Unfortunately, John Grabow saw to it that that wouldn't matter, walking in a run in the eighth and allowing three more after that. Grabow's a good pitcher, so it's probably just one of those things. It happens. Grabow isn't the cause of this losing streak. The problem is that the rest of the team isn't good enough to pick up the slack for him when he has a bad game, or a bad month.