Now he's trying to figure out a way to stop last year's Heisman Trophy winner..
Mississippi State (4-4, 1-3 Southeastern Conference) continues its brutal second-half schedule this week as it prepares for a road game against No. 11 Texas A&M and quarterback Johnny Manziel.
"That's why guys want to come here, because they want to play in those games," Mullen said. "You come to the Southeastern Conference to play in big games and we get another one this week."
It's already been a difficult week for the Bulldogs off the field. The mother of starting quarterback Dak Prescott died on Sunday after more than a yearlong battle with colon cancer.
Mullen said Prescott has returned home to Louisiana to be with family and isn't sure when he'll return. Mullen said backup Tyler Russell is healthy if needed against Texas A&M.
"We're a very tight-knit family program and when someone in our family has to go through something like that it's a very difficult situation," Mullen said. "Our prayers are always with him. Our prayers are with the whole family."
The Bulldogs are coming off a 34-16 loss to then-No. 14 South Carolina last weekend. Mullen said the offensive line did a pretty good job against South Carolina's star defensive end Jadeveon Clowney, who had three tackles and a tipped pass at the line of scrimmage.
But it didn't matter because of five turnovers that repeatedly gave the Gamecocks good field position. Prescott threw three interceptions and lost a fumble.
"There was a very different reason for each one of them happening," Mullen said. "And you have to give South Carolina credit — they were making plays and running to the football. Usually when you play hard and run to the ball, good things happen."
Mullen is hoping for a much cleaner game against the Aggies (7-2, 3-2).
Texas A&M continued its offensive onslaught last week with a 57-7 victory against Texas-El Paso. The Aggies have scored at least 41 points in every game this season and are leading the SEC with 49 points per game.
Manziel is having another extraordinary season, throwing for 2,867 yards, 26 touchdowns and eight interceptions. The 6-foot-1, 210-pound sophomore hasn't been quite as prolific on the ground, with 564 yards rushing, but he's still had his share of highlight-reel runs.
Another issue for Mississippi State is stopping sophomore Mike Evans. The 6-foot-5 receiver has caught 52 passes for a league-high 1,147 yards and 12 touchdowns.
"That's your problem," Mullen said. "You say we'll put two guys on Manziel and two guys on Evans, but then there are seven on the other nine and we're two short. That could be a problem. You look at all the talent they have and that makes them a good offense. What you have to do is you have to execute at a very, very high level."
But considering Texas A&M's offensive track record, it is unlikely Mississippi State will force a low-scoring game. That means it's on the offense to produce points and limit turnovers.
Mississippi State actually outgained South Carolina 385-307 in total yards on Saturday, but the five turnovers were too much to overcome. Texas A&M's defense has been forgiving at times this season — giving up 37.8 points per game to SEC opponents.
"It's a great challenge for our guys," Mullen said.