Joe Namath was like most Jets fans when he heard the news last week the team had fired general manager Mike Maccagnan.

It caught him off guard, but not because he thought Maccagnan had done a great job.

“Only the timing of it [surprised me],” Namath said Tuesday. “It wouldn’t have surprised me if it happened last year or if it happened three or four months ago. I know changes are constant if you don’t win.

“For years, I’ve wondered why the talent we get in here isn’t a little bit better. Who’s evaluating these people?”

The greatest player in Jets history sat down with The Post on Tuesday to discuss his new book “All the Way: My Life in Four Quarters” and the current state of the Jets.

Namath said Jets fans need to put their trust in owner Christopher Johnson despite their skepticism.

“I’ve watched and listened to some of the sports shows,” Namath said. “I saw cats coming down pretty hard on Christopher Johnson. It’s legitimate for fans to say, ‘Wait a minute, what are we doing here?’ But one thing I know is nobody wants to win more than Chris, than those players, than the people that are working there. We’ve got to trust that … well, you don’t have to, but I trust it. I know they’re trying hard to win.”

Namath lives in Florida and has watched new Jets coach Adam Gase closely over the past three years while Gase was the coach of the Dolphins. The Jets legend said he believes the franchise made a good hire.

“I liked him with the Dolphins. He disciplined that team,” Namath said. “He had bad luck down there and luck is a part of the game with injuries. I like the way the offense transformed when he came there. He had to weed out some attitude problems there and he still ended up with a decent record. I’m excited about him being here. I think he’s going to be a positive change.”

While Namath believes in the coaching, he thinks the Jets players need to start taking more accountability.

“What the players need to do, to me, is establish the leadership in that locker room,” he said. “When we watch games, we see our team beating ourselves, making mistakes, busting coverages, losing poise.”

Then, in his unmistakable voice, Namath gives what he feels is the key word, extending every syllable: “Disssss-ci-ppppppline,” Namath says.

“You play like you practice,” he said. “I know you can’t practice the way we play these days because you can’t have the physicality out there. But the mental part of the game, that is something you have to get and not beat yourself with it.”

Jets fans have been waiting for 50 years for someone to duplicate the magic Namath brought to their team. For his book, Namath went back and watched Super Bowl III. The book has him looking back at that game and then reflecting on his life. Namath said it was the first time he watched the game that made him an icon since 1969 when he watched the film at Shea Stadium.

“It brought back some memories — absolutely,” Namath said. “You see yourself perform not as well as you would like to remember you performed. You miss on a couple of throws … that kind of thing. I marveled at our defense and how they played. Matt Snell, Pete Lammons, our guys did not drop a ball. … There’s nothing about that game I’d change, 16-7 is right where it is, I promise you.”

Namath hopes that current Jets quarterback Sam Darnold can bring the team back to the promised land, but Namath hopes to see the Jets add more talent around him.

“Sam needs help,” Namath said. “We all do out there. You don’t do it on your own.”

The Jets signed WR Deonte Thompson on Tuesday. He has played for the Ravens, Bears, Bills and Cowboys. He played for Jets coach Adam Gase in 2015 when Gase was the offensive coordinator in Chicago. Thompson also has returned kicks. The team waived WR Xavier Ubosi, who was picked up last week by former GM Mike Maccagnan.