SANTA CLARA, Calif. -- Cardinals defensive end J.J. Watt stepped down from the podium after his postgame news conference and, instead of taking the back way to the locker room to shower and get dressed before heading home to Arizona, he walked out to the hallway in the underbelly of Levi's Stadium and headed back to the field.

Waiting for him were his wife, Kealia, and 2-month-old son, Koa, for one more picture in uniform, one more moment after Watt's final game, a 38-13 loss to the San Francisco 49ers.

A short time before, Watt took his final steps off an NFL field when he was substituted out with 2 minutes left. The 49ers' offense had set up, ready to start the next play, when Watt began walking to the sideline. The big screen at the top of the stadium congratulated Watt, and the remaining fans broke out in a standing ovation. An official stood between the center and 49ers quarterback Josh Johnson, holding off play in order for Watt to have his moment as he slowly walked to the sideline.

Cardinals coach Kliff Kingsbury had seen that type of moment in basketball but never in football.

"That was special," he said after the loss.

Niners coach Kyle Shanahan called the reception "awesome" and "more than deserved."

"He was a problem throughout the game for us in the run game and the pass game. But for it to slow down there at the end and for him to have his moment where he could walk off, I think everyone in this country respects the hell out of him for what he's done on and off the field," Shanahan said. "He's an all-time great."

Watt finished the game with two sacks, giving him 12.5 for the season, making this the fifth best of his career, and 114.5 in his 12 seasons.

"I wish the game had gone differently in many ways, but I'm thankful and grateful and I'll always remember it, that's for sure," Watt said.

Sunday evening capped an emotional 24 hours for the 33-year-old.

It started at the Cardinals' team meeting on Saturday night.

Watt had been telling his defensive line coach, Matt Burke, throughout the week that he was trying to get emotional about retiring, but it just wasn't happening. Burke warned the three-time Defensive Player of the Year that something was coming that would do the trick.

At the end of the meeting, defensive coordinator Vance Joseph, who ran it, ceded the floor to Burke to introduce a going-away present to Watt: a six-minute video tribute.

Ever since Watt announced on Dec. 27 his intention to retire, Burke and a team from the Cardinals' video and social media departments worked to gather videos from friends, family and people around the league. They were slow to come in during the first week.

"This is going to be the all-time backfire," Burke remembered saying.

Then they started pouring in. Peyton Manning, Tom Brady and Aaron Rodgers were the biggest football names who shared their memories of Watt, according to Kingsbury.

Watt's youngest brother, T.J., was the first video in the tribute. That's all it took for J.J. to break down.

"I absolutely lost it," Watt said. "I was bawling like a baby, and I didn't stop until long into the night. 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, teammates, coaches, opponents, it hit me in a different way that I never expected."

The video, which was comprised from 30 minutes of raw footage, which the team plans on splicing together and sending to Watt, was capped by a video from Kealia.

J.J. called it one of the "greatest" gifts he's ever received.

"You feel responsibility to sort of shepherd him out the right way," Burke said. "And hopefully, hopefully that's some memories for him. Two sacks don't hurt, either."

It took Watt longer than normal to fall asleep Saturday night, but the emotions were about to get kick-started again when he awoke.

One of the first things he saw after waking up Sunday was a photo of his brothers, Derek and T.J., a fullback and linebacker Pittsburgh Steelers, respectively, walking into Acrisure Stadium each wearing one of J.J.'s Cardinals jerseys.

J.J. lost it again.

"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," he said.

Watt's wife, son and parents flew in from Phoenix on a flight that landed at 8:40 a.m. local time, and they drove straight to the Cardinals' hotel. In a first for Watt, he was giving Koa a bottle four hours before kickoff.

"It was the first-timer. It was the first-timer," Watt said. "That was really cool. It was time to eat. So, he doesn't give a s--- that I got a game to play. He's hungry."

Then Watt went out and played 83.6% of the Cardinals' defensive snaps and finished with two sacks, five tackles -- three of which were for a loss -- and a pass deflected.

Watt joked that he should've had his son in attendance for all his games because of how well he plays when Koa is there.

Watt, however, played Sunday like he wanted to in his last game.

"I said I wanted to go out playing good ball, and I'm playing good ball," he said. "I know I still can, I'm just choosing not to, that's all."

The plan was to let Watt "go to the wheels fall off," Kingsbury said.

"You don't want to come out of the game, but they've got backups in and you don't want something bad to happen, but, I mean, what was I saving it for?" Watt said with a laugh. "I'm gonna have a s---load of drinks tonight, so it don't matter. Like, whatever, it's over."

Sunday's send-off reminded Watt and his mother, Connie, of his goodbye at Wisconsin, where he left after his junior season. He could've come back and continued to play at a high level but knew it was time to leave.

He's going to try to celebrate a bit this week, maybe play nine holes of golf in the middle of the week, and then he, Kealia and Koa are going to fly back to Wisconsin and spend time up there with his family and friends and celebrate his career some more.

"I don't know beyond that what it looks like," he said. "It's very strange. It's very strange."