There were plenty of valid reasons to believe the Tennessee Titans offense would regress in 2020. 

Those reasons started with the performance of Ryan Tannehill, who after taking over for Marcus Mariota in Week 6, completed 70 percent of his passes at an average of 9.6 yards per attempt, the best figure in the NFL. He threw 22 touchdowns against only six interceptions, giving him a league-best 117.5 passer rating. To say those figures were out of line with his performance during his time in Miami would be a dramatic understatement. Tannehill completed 63 percent of his passes at an average of 7.0 yards per attempt with the Dolphins, throwing 123 touchdowns and 75 interceptions while registering a 87.0 passer rating. It was more than reasonable to expect Tannehill to take a step backward this season, even if you still thought he'd remain a quality contributor. 

The second reason to expect a step backward was that it figured to be remarkably difficult for Derrick Henry to repeat his extraordinary efficiency. Through the first six weeks of last season, Henry averaged only 3.7 yards per attempt and scored four touchdowns. Once Tannehill took over, Henry took off: he ran for 1,124 yards and 12 scores in nine games, averaging an absurd 5.9 yards per attempt along the way. With the Titans losing star tackle Jack Conklin in free agency, it seemed reasonable to expect at least a minor step backward from Henry, even if you still thought he'd remain one of the league's better backs.