Jim Boyce, a FIFA vice-president from Northern Ireland, said "Eriksson performed well" in Barcelona's 2-0 win at the Etihad Stadium.
Pellegrini claimed Eriksson, who awarded a penalty against City and sent off Martin Demichelis, had "not been impartial".
Eriksson, 39, has been selected by FIFA for the World Cup finals in Brazil.
Jim Boyce: "It is absolute nonsense to say a referee should not be chosen for an important match because he comes from a smaller country.
"If the referee has proved himself at the top level it should not matter what country they come from.
"All the referees who have been chosen for the World Cup have been assessed by experienced officials who have been involved at FIFA and UEFA level and marked on their performances in the World Cup and confederation competitions at a high level.
"I read the remarks that were made by the Manchester City manager. I saw the game and my own personal opinion is that I thought the referee had a good game. He is a very experienced referee who has been chosen for the World Cup because of excellent reports of his performances in Europe."