Yes but something weird is going on with Malcolm Jenkins. He reduced his salary for the last two years of his contract to the vet minimum and received nothing in return for it. Maybe he is just doing the team a solid to giving them cap space because he wants to win more than make money. But that doesn't seem very likely.
But, this is also what Brees did before he retired last year. It allows the team to have cap space and then designate Jenkins as a post June cut and split the cap hit from his dead money over two years.
So, if Jenkins does end up retiring, Mathieu would be an excellent option at SS for us. In fact, he probably fits better at SS in our system than at FS.