Redknapp believes despite the disappointing final outcome, it was a worthwhile experience to see some of his fringe men, like former Gunner David Bentley, get a taste of first-team action.
"I wanted to rest a lot of the payers who have played a lot of games," Redknapp said.
"Sandro got around the pitch. I like him. I think he will be good player. I learned that Sandro can play in this country, for sure.
"It was Bentley's first game, and he needs his match fitness. I am sure he was very tired at the end of extra time."
Redknapp added: "I cannot keep playing the same guys in every game - Sir Alex Ferguson made 10 changes for a Champions League game.
"We had eight international players out there at the start, and five of them played at the World Cup, so with a couple of kids, it was a nice mixture.
"We have got West Ham on Saturday, then a Champions League game here, before Aston Villa on Saturday - it is non-stop."