With his team playing on just a day's rest, Costa Rica head coach Jorge Pinto made a number of changes to his squad from the opener. The modifications, though, did not prevent the host from firing on all cylinders against its northern neighbor.
In just the sixth minute, a Celso Borges cross was headed in by Cristhian Lagos, giving Costa Rica the early lead.
The Ticos continued to press, but despite numerous close calls - including a Borges drive in the 45th minute that required a sterling save from goalkeeper Justo Lorente - they couldn't extend their lead before half time.
The second half was much of the same, with the local side pushing towards the Nicaraguan goal in waves, while the scrappy Pinoleros did their best to possess and move the ball forward.
Despite positive intent from both sides, the narrow difference would hold until the 87th minute, when the Ticos put the game away. An Ariel Rodriguez corner kick found the head of an unmarked Borges, who neatly headed in to provide the final, 2-0, score line.
Costa Rica, which has won six Central American championships and has appeared in 10 previous Gold Cups, is unbeaten in 11 of its last 12 UNCAF games. Nicaragua is winless in six consecutive Copa Centroamericana outings.
The victory clinched first place in Group A for Costa Rica, which faces second-place Guatemala on Tuesday night. Nicaragua and Belize - both still very much in the hunt for a semifinal spot and accompanying CONCACAF Gold Cup berth - will face off on Tuesday.
To watch highlights of the Costa Rica-Nicaragua match, click here.