It was the decision of Rivera and general manager Dave Gettleman to release Carolina's all-time leading receiver in March.
Smith, 35, played a big part in Baltimore's victory, catching seven passes for 139 yards and two touchdowns.
“First of all, I’m not a sore loser,'' Rivera said in explaining why he sought out Smith. "Secondly, I’ve got a tremendous amount of respect for who Steve is and what Steve’s done for this team, and what he’s done for me personally.
"I just wanted to make sure I appreciated him. I didn’t get a chance to speak to him before the game, or during the game, or after the game immediately. But I wanted to make sure he knew that, that I had enough respect for him that I would come over and congratulate him and wish him the best of luck.''
Rivera said it was a quick conversation, but "nice."
"It was good to see him, and I think he knew that I have respect for who he is,'' Rivera said.