Don't think that was a red card whatsoever.
He gets sent off because his back leg leaves the ground which makes it look worse, but it's irrelevant to be honest. His tackling foot is basically on the ground by the time he makes contact with the ball (which he wins). It's not a high tackle, unlike Kompany's against us.
I can understand it being a foul and a yellow because of the follow through, but sending a player off for that is killing the game and essentially outlawing slide tackles.