In the other game of the day, giants Mexico felled Panama 3-1.
Defeats for St Lucia and Haiti came after both Jamaica and Trinidad and Tobago suffered bad results on Friday’s opening day of the tournament.
St Lucia were cut down by braces from Andy Reyes and Kevin Masis as Costa Rica produced a strong second half effort to run out easy winners.
Reyes gave the Costa Ricans the lead at half-time after scoring at the near post in the 31st minute and Masis nodded in Roberto Cordoba’s cross four minutes after the resumption, to put the Central American side in command of the contest.
Reyes added his second in the 52nd minute after being set up by Ian Smith and the blitz was topped off by Masis who collected a pass from Reyes and fired home from 17 yards out in the 68th minute.
Haiti, meanwhile, wilted after taking the lead against Canada, watching as their North American rivals hit back strongly to run away with victory.
The French side were in front on 32 minutes when Ronaldo Damus curled in a superb left-footer. Two minutes later, however, Canada were on level terms when Duwayne Ewart clinically put away Munir Saleh’s through ball.
Then, in first half stoppage, Canada took control of the encounter as Matthew Baldisimo headed in from close range for a 2-1 lead.
In the second half, Kadin Chung ended the game as a contest in the 73rd minute with a telling right-footer.
Both St Lucia and Haiti play their second games on Tuesday against Mexico and Panama respectively.