Jameson threw in a minor-league game Friday, Nick Piecoro of the Arizona Republic reports.
Jameson was one of several pitchers affected by the two-game rainout Wednesday and was adjusted to throw Friday. Arizona manager Torey Lovullo said Jameson showed excellent velocity on his fastball, which touched triple digits. The manager also said nothing should be read into the fact that he didn't pitch in a Cactus League game. Jameson is one of four starters still competing for the final spot in the rotation.