Giants closer Brian Wilson debuted a two-seam fastball against the Dodgers last week.
Wilson has added the pitch to a menu that typically has included a straight four-seam fastball, a cutter and a slider.
"The cat's out of the bag. It's another weapon," pitching coach Dave Righetti said, calling Wilson's two-seamer a "big-time" development.
Brian Wilson Unveils Two-Seam Fastball