Seems like more proof the guy is biased. Believe he was determined to call "safe", but realized it was just too clear and easy to see how bad the call would be.
Guys strike zone was ridiculously biased. The call at the plate just seemed like more proof, kinda like a Freudian slip. Ump was calling "safe" before the play even finished, then changed to "out" when it was just too obvious, IMO.