The Titans got stomped by the Texans on Sunday, losing 57-14, and the bad news didn't stop there.

The most concerning aspect of the loss? Quarterback Marcus Mariota left the game with a hamstring injury and didn't return. He'll get an MRI to determine the severity of the injury.

Before suffering the injury, Mariota ran for two touchdowns. On his second touchdown, which is when the injury occurred, Mariota rolled out to his right after play-action and beat Whitney Mercilus around the edge to the pylon.

Besides those two runs, though, it was a day to forget. Mariota went 6 of 10 for 96 yards, no touchdown, two picks, and a 52.5 passer rating.

In relief of Mariota, backup quarterback Matt Cassel was even worse, completing 4 of 10 passes for 21 yards. Two of his incompletions were picked off. His passer rating? 8.3. And the defense gave up 57 points to the Deshaun Watson-led Texans offense. So, the Titans certainly have more problems than their quarterback situation. 

But Mariota's injury deserves the focus. Without him, the Titans aren't the potential playoff team so many of us pegged them as before the season. Though he struggled on Sunday, Mariota's been pretty damn awesome since he entered the league in 2015. Before Sunday, Mariota had completed 61.5 percent of his passes, averaged 7.5 yards per attempt, thrown a touchdown on 5.2 percent of his passes and an interception on 2.2 percent of his passes, and accumulated a 93.0 passer rating.

Cassel, meanwhile, is not a starting-caliber quarterback. 

Next up for the 2-2 Titans are the 1-2 Dolphins, who have scored six points in their past eight quarters.