Giants starting pitcher prospect Christopher Heston continues to lower his ERA for Double-A Richmond. Heston hasn't allowed an earned run in four May starts, going 2-0 with 23 strikeouts and four walks in 29 innings. "I heard a lot coming into this (Eastern League) that it was more of a pitcher's league," Heston told The Richmond Dispatch. "The ballparks are pretty fair to pitchers. But overall, the mentality doesn't change. Try to throw quality strikes down in the zone. Try to let (hitters) make contact. Try to keep myself in pitcher's counts. It's been working, so far." Heston is 4-2 with a 0.61 ERA and .186 opponents' batting average in nine starts. He also has 48 strikeouts in 58 2/3 ...