In their past three internationals, Costa Rica have failed to score, losing 1-0 to Australia, 4-0 to Chile and 1-0 to South Korea.
But in all three of those matches, neither captain Bryan Ruiz nor leading striker Alvaro Saborio have played - the last two players to hit the back of the net for Costa Rica.
Ruiz and Saborio both scored in Costa Rica's 2-1 win over Mexico in October last year.
Saborio has the most goals (31) of any of Costa Rica's active players but remains well adrift of all-time goal-scorer Rolando Fonseca (47).
Costa Rica coach Jorge Luis Pinto has picked a strong squad with the likes of Joel Campbell, who scored for Olympiacos against Manchester United in the UEFA Champions League last week, Celso Borges (AIK Stockholm), Junior Diaz (Mainz) and Christian Bolanos (Copenhagen).
Pinto's team will come up against another out-of-form side with Paraguay winless in three games too.
Paraguay lost their last three World Cup qualifiers after knocking off Bolivia 4-0.
That win against Bolivia was followed by a 5-2 thrashing at the hands of Argentina, a 1-1 draw in Venezuela and a 2-1 loss to Colombia.
Paraguay did not qualify for Brazil 2014 but should provide Costa Rica with a tough hit-out in one of Pinto's last opportunities to look at his players before naming a squad to go to the World Cup.
In the past two meetings between the two countries, Paraguay has won both times, knocking off Costa Rica 2-0 in a friendly in 2010 and 1-0 in the 2004 Copa America.
Paraguay's chances of victory will likely rest on the shoulders of experienced trio Nelson Valdez (Olympiacos), Cristian Riveros (Gremio) and Victor Caceres (Flamengo).
