McAllister told LFC TV: "Mascherano has shown his class since arriving here. It didn't happen for him at West Ham in a move that I thought was strange to begin with.
"Now he is surrounded by quality players and is really showing his worth.
"For me, he was the one who stood out against Birmingham at the weekend. He's one of the cleanest tacklers of a football I've ever seen. Every time he looks to be in trouble he manages to come away with the ball."