Over the past four seasons, J.J. Watt was building a case as the greatest defensive player ever. After a solid rookie season, Watt exploded. The Houston Texans defensive end had 69 sacks over the past four seasons. He won three NFL defensive player of the year awards. Nobody can match that four-year run. Not Reggie. Not Deacon. Not Butkus. Not L.T. And when Watt was given his third defensive player of the year award last February, he was only 26 years old.