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Frank Ryan led the NFL in passing touchdowns twice. He led his team to an NFL championship. He once threw three touchdowns in a shutout victory in a title game. He won 65 percent of his NFL starts.

Unless you live in Cleveland or are over 50, you probably have never heard of him.

Ryan was Jim Brown's quarterback and then Leroy Kelly's quarterback. Hall of Fame receiver Paul Warfield was on the receiving end of many of Ryan's touchdowns. But don't write him off as some 1960s product of the system. Ryan threw five touchdown passes and ran for a sixth to beat the Giants and lead the Browns to the NFL championship in 1964. He then led three fourth-quarter comebacks to bring them back to the playoffs in 1965. With Warfield hurt nearly all of that season, Ryan helped make a Pro Bowler out of receiver/punter Gary Collins.

Ryan made three Pro Bowls, but All-Pro status was blocked by a couple of guys named Johnny Unitas and Bart Starr. His career was cut short by injuries suffered in the first of those three Pro Bowls. The Colts accused Ryan of running up the score in the 27-0 championship rout of 1964. A Colts defender delivered some payback in the all-star game. Ryan needed surgery and was in constant pain for the rest of his career. Yet he still led his team to the playoffs three more times.

The Pro Football Reference Similar Players tool compares Ryan's five-year peak to that of Joe Theismann. That makes sense: Both started their careers late, played with workhorse running backs, won a championship and had their careers curtailed by vicious hits.

But everyone remembers Joe Theismann.

There have been many better quarterbacks than Ryan in NFL history. But none accomplished more than Ryan while receiving less acclaim. By being overshadowed by Brown, achieving his greatest success just before the dawn of the Super Bowl era and getting stuck behind the Tom Brady and Peyton Manning of your grandfather's generation, Ryan earned the title of the NFL's All-Time Most Underrated Player.

Let's hope the fame doesn't go to his head.