Sevilla will host Gladbach in the Europa League round of 32 on Thursday with goalkeeper Beto, full-back Coke, midfielder Stephane M'Bia and forward Iago Aspas all unavailable through injury.
But Favre reckons it is laughable to suggest the reigning Europa League champions will be seriously hindered in the first leg at the Estadio Ramon Sanchez Pizjuan.
"Is that a joke?" Favre asked at a media conference, when a Spanish journalist claimed Sevilla might be weaker.
"Sevilla always put out a strong side. They have so many good players that they'll make up for the other players missing."
Favre added: "They are defending champions and that says a lot about their quality."
Beto has been Sevilla's leading goalkeeper this season, while Coke and M'Bia have started over half of the club's La Liga matches this term, and Aspas has been a regular option off the bench for coach Unai Emery.
Gladbach are in a much better situation heading into their away leg in Spain with Favre's squad fully fit.
Defender Roul Brouwers added that the Bundesliga club are in great shape mentally having won three of their four league games since resuming after the winter break, including a 1-0 derby win over Cologne on Saturday.
"The derby win has given us a lot of confidence," the 33-year-old said.
"We're playing well at the moment and we want to show that in Sevilla."
