The base coach can tell the runner anything he wants to. His only restriction is that he can’t touch the runner.
About the only job the first base coach has is to yell “BACK!” on pickoff throws.
Dry–it was the Angels, who were fooled twice in a month by the Red Sox’ Marty Barrett in (I’m guessing here) July of '86 (maybe '85)–I saw one of these, at Fenway in an afternoon game.
Actuallly, I didn’t see it, of course. That’s the beauty of the HBT—no one actuallly sees it, you just say “What the hell!?” and try to figure out why the runner is leaving the field and another out is recorded.
The Dodgers got us on this one in LA… mid-80s, I’m guessing. Brett Butler stole second, the SS covering looked helplessly at center field. Butler looked for the ball, back at the SS, and took off, when he he promptly tagged by the SS. Great centerfield shot of Butler laughing like a goofball.