The Brazilian made another big howler when Fulham scored their first goal at Craven Cottage.
Andre Johnson netted Fulham’s second goal while Spurs sub Frazier Campbell scored a late consolation goal.
“It was a disappointing day,” admitted Redknapp. “We started in second gear and suddenly looked like we were getting into the game until we gifted them a goal.
“It was a farcical goal, but he’s my goalkeeper. He’s got to do the job. This is the situation I have.
“I have Gomes and another goalkeeper, a Spanish lad who is 37, and then you have kids.
“Gomes is the first-team goalkeeper. His record at PSV Eindhoven tells you he was a world-class goalkeeper. He made some great saves after the goal, so I have got to keep believing in him and stay with him.
“The goalkeeping coach has got to work with him. I always think goalkeepers and their coaches have a special relationship and he’s got to get into his head this week.
“Fulham started sharper than we did and deserved the win. Their front two of Bobby Zamora and Andrew Johnson were excellent. They gave us problems.
“I brought Aaron Lennon on to try and give us some width but things didn’t happen for us today. We also look vulnerable from corners at the moment which is a problem.”