Bielsa managed Zanetti at Newell's Old Boys and sees the Argentine's versatility in Dallas.
"Those two players are very like Dallas in terms of their versatility. Dallas is a very potent, powerful player and can play with either foot.
"He's good at defending and has the capacity to make runs that allow him to flourish in the middle. He has a change of rhythm and surprise when he attacks. It's very difficult to find all of that in just one player.
"In the majority of the games that the team have played, he has been one of our best players."