So basically, from what I've read, here's what the papers claim regarding the clubs that are linked with Mahrez:
Chelsea, Tottenham, Barca (L'Equipe); Barcelona, Arsenal (AS), Manchester United (Yahoo).
Basically, only one club is being interested according to more than one source. And that is Barcelona.
Honestly, it makes more sense that Arsenal gets him to replace Sanchez or Barcelona gets him if they can't get Coutinho.