Messi, who has now found the net 37 times in 24 La Liga appearances this season, equalised with a simple tap-in, before sealing victory with a curling 25-yard free-kick.
"Messi decided the match," defender Jordi Alba told Barcelona's official club website. "301 goals for Messi - whatever anyone says will come up short."
Midfielder Sergio Busquets said: "He improves on a daily basis. He's the best in the world."
Dani Alves added: "Playing next to Messi gives you a lot of calm. It makes it easier to get things done."
Of Messi's 301 Barca goals, 206 have come in La Liga, while 56 have been scored in the UEFA Champions League.