CHARLOTTE - The Carolina Panthers have fired two defensive assistants in the wake of the team's four-game losing streak.

Ron Rivera relieved defensive line coach Brady Hoke, and assistant defensive backs coach Jeff Imamura of their duties on the Monday after the team lost to Tampa Bay, 24-17.

According to NBC Charlotte's Kelsey Riggs, that was the extent of the changes, meaning Defensive Coordinator Eric Washington, and the main defensive backs coach Richard Rodgers, remain in their positions.

But Rivera will "handle play-calling duties" on defense.

“In my judgment, I felt this was best for the team moving forward,” Rivera told the team's website. “These are always difficult decisions, and I thank Brady and Jeff for their hard work.

After beginning the season 6-2, Carolina is 6-6, with a narrow chance to make the postseason with four games left.

The defense, normally Carolina's calling card, has been an issue. The Panthers have given up 25.5 points per game, 21st in the NFL.

A CBS Sports report on Sunday morning said that new owner David Tepper is "getting antsy" during the team's struggles, and is considering "major changes."