No. 2 most underappreciated player in Titans history: Billy Volek, QB
Steve McNair is one of the most prominent players to ever play for the Titans but he wasn't nearly as good near the end of his stint in Nashville. Sure, he made the Pro Bowl in 2005 but the team's brass moved on from him after that season and drafted Vince Young to take his place. Also, injuries forced McNair to miss 12 games in his last three seasons with Tennessee, which takes us to Billy Volek, who shined during his absence.
After going undrafted in 2000, Volek signed with the Titans. Although he only attempted 72 passes in his first three NFL seasons, the former Fresno State Bulldog would get his chance to shine in 2004. That year, he made eight starts and completed 218 of 357 passes for 2,486 yards with 18 touchdowns and 10 interceptions.
Those numbers might not pop off of the stat sheet nowadays but NFL rules at that time didn't favor offenses as much as they do now, so that kind of production would be akin to flirting with the 4,000-yard mark these days.
Granted, Volek went 2-6 in those contests but he put on display his ability to sling the pigskin. As a matter of fact, he had one of the most productive two-week stretches any quarterback had had at that point in time.
Against the Kansas City Chiefs in Week 13, he logged 426 yards and followed that up with 492 yards and four touchdowns against the then-Oakland Raiders the following game. The Titans lost both outings and Volek returned to the sidelines next year.
Volek then spent five unremarkable seasons with the then-San Diego Chargers before hanging up the cleats in 2012. While his career path wasn't very different from those of many players, he was given a chance to shine and made the most of it, even if he wasn't able to win many football games.