http://m.mlb.com/video/?content_id=33122405&c_id=mlb
about 15 seconds into the video we see the runner run past the fielder who appears to be looking towards third/home while moving the ball to his throwing hand.
Umps gathered and met about the call and eventually called him out.
it looks as though there was really no play on runner until the runner has passed the fielder. While he is looking at home to check the runner and no play on the runner so no baseline is established.
I thought it was a correct call of safe.
Had a very similar call about two weeks ago......I stayed with the safe call at third.