The set-up: This isn't the most interesting match-up on the mound, but all things considered I believe it's one that favors the home side. The Reds send the erratic Luis Castillo to the hill, while the Nationals go with improving Tanner Roark.

The pitchers: Castillo is so far 6-8 with a 4.98 ERA. He most recently went seven shutout innings in a win over the Phillies on Sunday, striking out nine and walking just one. It was his best start of the year, but I think he'll make a predictable fall back down into mediocrity again tonight. Note that he's just 2-5 with a 6.44 ERA on the road as well still.

Roark is so far 5-12 with a 4.37 ERA. He most recently gave up one run off four hits over seven innings, while striking out seven and walking none in a win over the Mets on Tuesday. Over his last 15 innings of work Roark has given up just one earned run.

The pick: Roark has struggled overall this year, but his recent form suggests that the hard-throwing right-hander is finally trending in the correct direction. Castillo had an amazing performance in his latest start, but he's been consistently inconsistent all season, especially on the road. That makes Roark well worth the price of admission in this match-up in my opinion. Play on the Nationals.