He helped Mississippi State hang 30 points on UAB two weeks later, then threw his first college touchdown pass the following weekend in a 33-21 loss to Tennessee. He tossed TD passes on the first two possessions of a 31-14 win at Kentucky and also put up 31 points in a loss at Arkansas.
Carroll finished the 2007 season with 1,392 passing yards and Mississippi State finished with an 8-5 record that included a Liberty Bowl defeat of Central Florida. It was quite a debut season for a true freshman. That's why Croom smiled when a reporter at SEC Media Days earlier this week asked why the coach brought a sophomore to the proceedings, instead of a senior.
"Because he knows how to win," Croom replied.
Carroll's transformation from unheralded freshman to proven winner last fall surprised even his head coach.
"The guy starts off as a third-stringer," Croom recalled. "He didn't have a great arm ... still doesn't have a great arm. He ends up all of a sudden starting in the Southeastern Conference as a pure freshman – no benefit of spring practice, no working in the summer with the coaches, learning a pretty complicated offense.
"He goes out there and throws 135 or 136 straight passes without an interception, which almost broke the national record. And he wins more games than any quarterback at Mississippi State in the last eight years."
Looking back, Carroll sees the 2007 Tennessee game as something of a turning point.
"I remember that was my first game that we had a passing touchdown with me under center," he said. "That's when the game kind of clicked. I started to really understand and was able to dissect defenses. From there, it seemed to get easier."
He took another big step at Kentucky, throwing a touchdown to cap the Bulldogs' first possession, then throwing another to cap the second.
"Two consecutive drives with two passing touchdowns," he recalled, permitting himself a soft smile. "You can't ask for much more from an offense that was criticized last year for not being able to move the ball efficiently."
There is nothing imposing about Carroll, from his 6-0, 190-pound frame to his arm strength. He shows a knack for playing well in the fourth quarter, however, no matter how he played in the previous three quarters.
"I compare quarterbacks to pitchers a lot," he said. "If you give up a home run, you've got to forget about it and go to that next batter. It's the same thing at quarterback. You have to forget about making a bad read, throwing an interception, hurting your team. You've got to go out there and get the next drive going.
"Coach tells me it's an old-school offense we have. It's the West Coast but it's just managing the game the first 3½ quarters, then having the edge in the last five minutes of the game. That's how we won several of our games, and that's really all that matters ... coming out with that W."
Carroll does a good job of "coming out with that W," especially for a guy who is not blessed with a big-time arm. He says his lack of velocity is no problem, especially in the West Coast offense Mississippi State runs.
"It really doesn't bother me," he said. "If anything, it may be a little motivation. As long as we're winning, that's all that matters. I'm not worried about people saying my body's not the right size, I'm not the right height, my arm is whatever it is.
"In the West Coast offense you don't have to have the gunslinger arm. You just have to have an accurate, effective arm. More than anything, it's mental at quarterback in that system."