Chen vs. Gonzalez tonight in finale of beltway series

The Battle of the Beltway series concludes tonight at Camden Yards with a scrap between southpaws. The Orioles are sending Wei-Yin Chen to the mound, and the Nationals are countering with red-hot Gio Gonzalez. Chen is 3-4 with a 4.89 ERA in eight career interleague starts, and 0-2 with a 7.71 ERA in two starts against Washington. He's allowed eight earned runs in 9 1/3 innings. Chen has surrendered three earned runs or fewer in six of his last seven outings this season, though he's completed seven innings only once. It's good for Chen that the Nats aren't starting Stephen Strasburg tonight. The right-hander is 2-for-2 with a home run against him. Adam LaRoche is 2-for-3 with a home run. Left-handers are batting .327 against Chen this season, which could influence the Nats' lineup. We'll see. Gonzalez hasn't permitted a run in his last three starts spanning 21 innings. He's allowed nine hits and struck out 19. Gonzalez is 1-3 with a 3.75 ERA in six career starts against the Orioles and 1-1 with a 2.79 ERA in three starts at Camden Yards. Nick Markakis is 5-for-16 (.313) with a double and three RBIs lifetime against Gonzalez. Nelson Cruz is 0-for-10 with four walks and three strikeouts. Adam Jones is 4-for-19 (.211) and Delmon Young is 4-for-20 (.200). Steve Pearce is 2-for-6 against Gonzalez. He's got one hit in his last 10 at-bats over three games, and three hits in his last 19. Time to heat up again. The Nats are batting .281 against left-handers this season and .234 versus right-handers.