In the 2004 NFL Draft Manning was initially taken by the San Diego Chargers, while Rivers was picked up by the Giants with the sides having a deal in place to trade.
Then-Giants general manager Ernie Accorsi struck up the deal, and Coughlin says that neither player or team should have any regrets.
He told Giants.com: "I remember Accorsi making that deal. He was of 100% in belief that this was the right thing to do for our franchise. I remember that Ernie had studied Eli since he was a freshman in college and had really a strong, strong feeling about him.
"He had the confidence and the constitution to push the deal through. And it wasn't an easy deal to make. But it was a move that he made with great conviction.
"Philip Rivers has had an outstanding career in San Diego and Eli Manning has had an outstanding career here, so I think you have a win-win situation there."
Manning has twice led the Giants to Super Bowl victory since he became the team's starting quarterback. However, he has lost both times he has faced the Chargers in his NFL career.