Josh Heupel understands the challenge Tennessee faces this week in a Missouri defense that has proven to be one of the best around.

“They got some different personnel from the previous year on their roster,” Heupel said on the SEC coaches media teleconference. “… Guys who were there a year ago did a good job developing. … They’ve handled everything offenses are throwing at them extremely well. It’s difficult to run the football and they’re really efficient against the pass, as well. … Third downs, they’re making it difficult on the quarterbacks.”

About Brady Cook, Heupel noted the Mizzou quarterback’s development.

“He’s got a good command of what they’re doing,” Heupel said. “… As much as anything, he’s a relentless competitor. … I think he’s grown throughout the course of the season.”

Heupel, who was previously Missouri’s offensive coordinator, reflected on his time there.

“First of all, you think about the relationships with players and staff members,” he said. “I still stay in touch with some of those guys. … Proud of what we did and what we built.”

The Vols and Tigers will meet at noon ET on CBS.