The defensive end registered two sacks in his final career appearance, a 38-13 loss to the San Francisco 49ers, receiving a standing ovation when he was removed from the action in the final two minutes of the game.
An official stood between the 49ers center and quarterback Josh Johnson, holding off play to allow Watt to have his moment, which continued the tributes for the 33-year-old.
In a team meeting on Saturday, Arizona defensive line coach Matt Burke played a six-minute video tribute to the three-time Defensive Player of the Year – which included messages from his family, alongside the likes of Peyton Manning, Tom Brady and Aaron Rodgers.
J.J's youngest brother, T.J., was the first to appear in the video and sparked tears, before both he and Derek Watt made significant contributions in the Pittsburgh Steelers' season-ending win over the Cleveland Browns.
"I absolutely lost it. I was bawling like a baby, and I didn't stop until long into the night," he told reporters.
"I mean, the highlight videos are great, all the plays are cool, but when you hear from the people in your life that are important, from my family, from my friends, and then you hear from people you have the utmost respect for, team-mates, coaches, opponents, it hit me in a different way that I never expected.
"There's no way to explain what it feels like to anybody because the love that I have for them, the pride that I have for them.
"How much fun I have watching them, and then they walk in wearing my jerseys and T.J. gets whatever he had [a half-sack], Derek scores a touchdown.
"I mean, I wanted to win today, but for our family, I couldn't ask for a better send-off.
"I want to thank the 49ers, that was very classy, and their fans, they didn't have to do that. I appreciate them doing that, that was better than I could have expected certainly from that standpoint.
"[I] had my wife and son here and my parents here, I'm thankful and grateful, and I'll always remember it that's for sure."