Now losers of three straight, it's the Chargers' first 2-5 start since 2015.
"I'm going to come in and I'm going to work my ass off for the rest of the season. I can't control anybody else," defensive end Joey Bosa said of the loss, according to ESPN's Eric Williams. "I know we have a lot of guys that want to win, and we'll see who's with me on Monday.
"You can find out who wants it pretty quick after a game like that."
Gordon's fumble at the 1-yard line came moments after Philip Rivers made a 16-yard pass to Austin Ekeler that was initially ruled a touchdown but then reversed, leaving the Chargers a yard short with 44 seconds left.
Consecutive penalties on back-to-back plays, one by each team, kept the Chargers at the Titans' 1-yard line and set up a likely game-winning touchdown scenario for Gordon. The running back dove into the end zone, but the called touchdown was reversed again after a review.
On the next play, Gordon ran one more time, but he fumbled, and Tennessee recovered.
"On the field, we won it twice," tight end Hunter Henry said. He added, "I looked at the sideline a few times like, 'That's the game.' To have that happen toward the end is one of the craziest games I've ever been in."
Third-year head coach Anthony Lynn said he still believes in his team.
"I told our players that 1 yard can bring us together, or tear us apart," Lynn said. "And with the character that we have in that locker room, I do believe this group will rally."
Sitting last in the AFC West, Los Angeles will try to end its losing streak in Chicago against the Bears next week.