Before the race, Redknapp said “we’ve come into the Champions League today”, and the victory is worth £142,375 to the 78-year-old.
Redknapp, who retired from management after leaving Birmingham City in 2017, was trembling as he spoke to ITV Racing moments after his winner was confirmed.
“It is a dream, to have a horse that good is unbelievable,” he said. “I love the game that much.
“To come here on King George day and just run made me so proud, but to have the winner is special. I am so lucky.”
Joint-favourite Jango Baie was a length back going into the final fence and was closing on the lead trio right up to the line.
“When they came to him, I thought he was beat and would finish fourth,” said Redknapp. “But he’s come again and the guts the horse has shown is just amazing.
“Everyone was jumping on me at the end and I didn’t know I had won.
“But we had a lot of support here today and I love the racing, I love the game, I love the people in it, so to have a winner on the big stage is fantastic.”