Tavarelli had his chance to prove himself in Jose Luis Chilavert's absence in the recent friendly against England, but he conceded four goals.
Admittedly two came from deflections and he was rarely helped by an extremely fragile defence.
But the 31-year-old, renowned as a profilic shot-stopper, has some way to go to reach Chilavert's lofty heights.
He looks likely to replace the Paraguayan captain, though, if he proves to be injured at any point through the tournament.