Following Canada's 7-0 thrashing of Cuba earlier on Sunday, Mexico needed at least a point to secure top spot and they took the lead just before the half-hour mark through Uriel Antuna, who raced down the right before cutting in and firing home inside the near post.
Martinique, who had already been eliminated from the playoffs picture, equalised in the 56th minute through an exquisite free kick from Kevin Parsemain, who curled the ball around the wall and into the top-right corner.
Mexico went back in front five minutes later when Raul Jimenez tucked away Rodolfo Pizarro's cross and it was 3-1 in the 72nd minute, Jimenez the provider this time, a smart touch through a pair of defenders for Fernando Navarro to rush in and score inside the far left post.
Martinique pulled one back when Jordy Delem headed home in the 84th minute, a goal that ratcheted up the tension and ultimately saw a frustrated Mexico coach Gerardo Martino issued a yellow card.
But Mexico, favourites to win the tournament that crowns the continental champions of North America, Central America and the Caribbean, saw the game out to deliver Martino his seventh consecutive win since taking over in January.
(Reporting by Frank Pingue in Toronto; Editing by Peter Rutherford)
