“Salah was hit by an injury, but played through it,” said Galal following his debut after Portuguese Carlos Queiroz quit because he could not agree terms for a new contract.
Galal told a press conference that Salah rejected a Liverpool request to have a pre-match scan on the undisclosed injury, but “that will be done now”.
Egypt face Ethiopia on Thursday in Malawi capital Lilongwe because their opponents do not have any international-standard stadiums.
Two-time African Footballer of the Year Salah has experienced two major disappointments with record seven-time Cup of Nations winners Egypt this year.
They lost the Cup of Nations final to Senegal on penalties in February and the following month fell to Senegal again in a shootout, this time in a 2022 World Cup play-off.