It's no secret -- Watson's been a shell of himself during his time in Cleveland ... with most members of the Dawg Pound begging the team to end their misery and bench the guy.

We asked Lombardi -- who served as general manager for the team from 2013 to 2014 -- what he thinks happened to Watson ... and he believes the $230 million he inked killed the version he was while a member of the Houston Texans.

"He's rich and is guaranteed rich," he said. "I wrote in my column, sometimes he goes to the sideline, he's got that towel over his head, he's checking his Bank of America account to make sure he's still filthy rich."

"He's lost his motivation, he's lost his drive, he's lost almost his pride to be great. I don't feel it; I don't feel the passion in him. He's guaranteed for the next two years."

Since the trade to Cleveland -- which included serving an 11-game suspension and a $5 million fine -- the numbers Watson has put up have been a far cry from his production as a Texan.

He has played in only 17 games since 2022 ... and in those games, he has racked up 3,069 yards, 19 touchdowns, and 12 interceptions.

Lombardi said the Browns are going through what he calls the "sunk-cost fallacy" and won't admit they were wrong about Watson -- even though everyone else knows it.

"Kevin Stefanski, this isn't about getting away from the contract," he said. "This is about saving your franchise. The players know it. They didn't even offer a contract to Joe Flacco, who took them to the playoffs last year."