SF Giants observations: Mahle working on slider, Haase hits grand slam

MESA, Arizona — With a revamped slider in his bag, Tyler Mahle made his first appearance in a Giants uniform on Saturday afternoon at Hohokam Stadium, tossing a scoreless inning with two strikeouts.

Mahle, who signed a one-year, $10 million deal to join San Francisco this offseason, has thrown a slider of some kind for most of his career. But the current version of the pitch, which he threw six times on Saturday, had more movement compared to last season.

Against the Athletics, Mahle...