Alfaro akaita mutambo wake wekutanga kuCosta Rica mumutambo waApril 1991 wekushamwaridzana neMexico uye akawana huwandu hwe27 caps, achiwana 1 chinangwa. Akamirira nyika yake mumitambo mishanu yekukodzera yeFIFA World Cup uye akatamba mu1999 UNCAF Nations Cup uye 1997 Copa América
.