Nebraska quarterback Taylor Martinez didn't start the third quarter after limping off the field at halftime. The freshman suffered a right leg injury late in the second quarter but finished the first half before being replaced by Zac Lee on the Cornhuskers' first series of the third quarter.
Martinez completed 6-of-9 passes for 115 yards and one touchdown. He also ran 12 times for 16 yards.
"He's okay, he just couldn't push off," said Nebraska head coach Bo Pelini on the status of Martinez. "He has a bone bruise, his x-rays are negative. He's going to be okay."
The Cornhuskers (7-1, 3-1 Big 12) defeated their second straight unbeaten opponent after winning at Oklahoma State last Saturday.
Blaine Gabbert threw for 199 yards on 18-of-42 attempts with one touchdown and one interception for the Tigers (7-1, 3-1), who were coming off the euphoria off a 36-27 triumph at home over then-BCS leading Oklahoma.
"I'm very disappointed in the way we played," said Missouri head coach Gary Pinkel. "I wish we could have played better but they certainly did the right things and played a very, very good game."
The Cornhuskers erupted for 24 points in a first quarter that was bookended by a pair of long touchdown runs by Helu Jr.
After the Tigers went three-and-out to begin the game, the senior running back sprinted 66 yards to the end zone on Nebraska's first play from scrimmage. Alex Henery kicked a 41-yard field goal on the Cornhuskers' next series, then Martinez and Kyler Reed hooked up for a 40-yard score before Helu Jr. capped the offensive onslaught with a 73-yard dash.
Missouri was forced to punt on each of its first four possessions, and a forgettable opening 15 minutes for the Tigers ended with Nebraska's DeJon Gomes picking off Gabbert on the final play of the first quarter.
The Tigers' De'Vion Moore ran for a 33-yard touchdown on fourth down to account for all the scoring in the second quarter.
Following the break, Gabbert guided the Tigers 78 yards and T.J. Moe finished off the 12-play drive with a 23-yard TD grab to make it a 10-point game with 7:30 remaining in the third quarter.
Helu Jr. responded less than a minute later by running for a 53-yard score.
Missouri drove to the Nebraska one on its next possession, but the Cornhuskers' defense forced the Tigers to settle for a 23-yard Grant Ressel field goal with 1:35 left in the period.
The Tigers possessed the ball for just one series in the fourth quarter and punted it away. The Cornhuskers used Helu Jr. to run out the final 8:40 of the game.
This game marked the final matchup between the two schools as Big 12 rivals. Nebraska will join the Big Ten in 2011...Gabbert ran for 74 yards on 22 carries...Moe caught five passes for 71 yards, while Michael Egnew had 70 yards on seven receptions for Missouri...Lee completed one of his three tosses.