More MLB Replay Confusion

Odd ending to the Pittsburgh v Arizona game. In the 10th, Pirates trying to turn an inning ending double play w/ a man on third, go to second and get the out, then the throw to first is blocked by the runner sliding w/ his arm up. winning run scores from third and game is over.

umpire rules no intent, but it's pretty clear from the view in line w/ first the runner's left arm was way out and wide to disrupt the throw, and apparently it's not challengable and would have only been a crew chief review.

Weird play, and the dudes w/ the headsets looked like they were going to hand them to the umps and the umps just kept walking past.

I'm not being a pirate homer here, i'm just pointing out how replay only works when it's used. i mean, you think w/ the game in the balance it would be worth a second look.

Weird game. Pirates had their chances.

Still photo from ESPN
Totally normal to have your left arm super up and high in the air in line w/ the potential throw, but your right hand down. I just have to think a 10 second look at the replay would have led to a pretty obvious ruling that he altered his slide to block the throw.

Video from MLB