Martinez believes he can rely on his £13m summer capture from Wigan in any situation.
He told the Liverpool Echo: "James is one of those players you sometimes don't appreciate but he's always there making sure the team has the right balance and what it needs.
"He allows others to shine.
"He can adapt to different situations during a game when you need him to because of the tactical awareness that he has.
"At the weekend you saw that influence in the manner that we were able to get men forward, and give us the momentum to make it hard for Villa to keep a clean sheet."
For breaking stories and all the great banter like us on Facebook: facebook.com/tribalfootball