There's a lot of stuff like 'don't bunt for a hit late in a no hitter', 'don't look back and see where the catcher is', etc., but this is the first I'm hearing of 'don't run across the pitcher's mound'.
Sandra
I remember when Pete Rose's hitting streak ended, he was pissed that the pitcher tried to get him out. He said he was entitled to see all fastballs in his last at bat.
Don't look back. Something might be gaining on you.
-Satchell Page