In 2020, the Bengals signed Texans defensive/nose tackle D.J. Reader to a 4-year, $53 million deal. At the time, it was considered a risky signing and an overpay, as Reader, while he had proven to be a solid tackle in his first few years, hadn't really broken out into a star player worth the amount of money the Bengals were giving him.
And, for his initial season in stripes, it looked as if the doubters would be right as five games into the season, Reader would suffer a leg injury that put him on Injured Reserve and effectively ended his season.
However, the former Clemson Tiger came back with a vengeance, proving himself in 2021 and 2022 as a dominating and vastly underrated run stuffer. What he lacks in getting to the quarterback, Reader more than makes up for in making opposing running backs-- even some of the best ones like Nick Chubb and Derrick Henry-- struggle to get yards each time they pound the ground. This signing was not only a great one in hindsight, but an overlooked one as well.
Of course, he's on this list because his four-year contract is soon due to be up, and his age (he will be 30 in 2024) and injury history (missed 20 games over the last three seasons) might be a deterrent to the front office, who may look at these factors and think they outweigh his impact on the field.
Even as a big fan of Reader, I would be hesitant to re-sign him to a long-term deal as injuries and age could very well slow him down.