DALLAS -- SMU made it interesting, but ultimately the Mustangs couldn't punch with the heavyweight Baylor Bears.

The fourth-ranked Bears asserted control, perhaps a bit later than expected, and repelled feisty SMU 56-21 on Friday night at Gerald J. Ford Stadium.

Baylor scored on four straight possessions in the second half to finally run away with the season-opener. In doing so, Baylor began to put a disappointing Cotton Bowl loss at the end of last season and a tumultuous summer behind it.

"We got to right a little bit of a wrong today from the Cotton Bowl eight months ago," Baylor coach Art Briles said. "So now maybe that Chick-Fil-A sandwich will taste good."

A Bears defense that struggled to get a grip on the Mustangs early, clamped down on SMU in the second half. Baylor gave up just 67 yards in the third quarter after surrendering 255 in the first half.

That gave the Baylor offense the chance it needed to blow open the game.

Already ahead 28-21, Baylor quarterback Seth Russell hit wide receiver Jay Lee for touchdowns of 22 and 41 yards late in the third quarter. Russell kept it going with a 57-yard scoring strike to wide receiver Corey Coleman early in the fourth quarter.

Briles said he got a chance to see how team reacted to adversity in its season opener.

"When things go bad and they had all the momentum in the second quarter, you could just feel it," Briles said. "You hang on. You hang on and keep fighting to try to make plays, and I thought our guys did a great job of just staying the course."

Baylor's barrage of points spoiled what had been a promising debut for SMU first-year head coach Chad Morris. The Mustangs were coming off a 1-11 season, which began with a 45-0 loss at Baylor in 2014. But SMU competed with Baylor well into the second half before the Bears' firepower took over.

Morris said he was happy but not satisfied.

"Obviously not the end result that we were hoping for," Morris said. "I'm extremely proud of the way our guys played. We're going to celebrate that, but the days of the moral victories at SMU, this feeling that we have in our stomach is unacceptable."

Russell, in his first game as Baylor's full-time starter, completed 15 of 30 passes for 376 yards and five touchdowns with one interception. Coleman caught five passes for 178 yards and a touchdown, while Lee hauled in three scoring passes.

Briles said he was encouraged by Russell's performance overall.

"I thought he really had the ball on the money," Briles said. "He's just good. I'm a little surprised there were that many incompletions, but that is stuff we'll have to work on. This is the first time the guy has ever walked out and started a game in an environment like that."

SMU quarterback Matt Davis finished with 166 passing yards with two touchdowns and two interceptions and rushed for 115.

Both the Baylor and SMU offenses began the game moving at blazing speed.

Baylor took the opening kickoff and traveled 75 yards for a touchdown in four plays. Russell ignited the drive with a 42-yard pass to Corey Coleman on the first play. Bears running back Devin Chafin capped the march with a 3-yard touchdown run.

But SMU answered and raised eyebrows within seconds. Mustangs quarterback Matt Davis hit wide receiver Courtland Sutton for a 46-yard touchdown pass on SMU's first offensive play, tying the game at 7.

The Bears and Mustangs followed that script for one more touchdown drive apiece. Russell ran 4 yards for a touchdown to cap another Bears' 75-yard touchdown drive. Then SMU punched back with Xavier Jones' 4-yard touchdown to tie it at 14 with 7:02 left in the first quarter.

Baylor threatened to pull away when Russell threw touchdown passes of 7 yards to Lee and 36 yards to KD Cannon late in the opening period for a 28-14 lead.

However, SMU shut out the Bears in the second quarter and the Mustangs cut Baylor's lead in half when Davis connected with Sutton for a 31-yard touchdown.

The Mustangs came close to tying it at the half when defensive back Shakiel Randolph picked off a Russell pass at the 50. Randolph's return set up SMU at the Bears' 33, but the Mustangs squandered the scoring attempt.

After SMU gained a first down at the Baylor 3 with 43 seconds left, Baylor linebacker Grant Campbell sacked Davis on third-and-goal. The Mustangs were out of timeouts and couldn't get the field goal team on the field before the half expired.

"Matt knew better," Morris said. "He came up to me and said, 'Coach, I knew better. I should've thrown it away.' It was disappointing right there. It's going to be a valuable teaching experience for us to get the ball out and come away at least with a field goal."

NOTES: Baylor suspended starting DE Shawn Oakman and starting S Orion Stewart on Thursday for unspecified violations of team rules. The suspension is expected to be for one game and the two players will return for the Bears' home opener on Sept. 12 versus Lamar. ... Baylor edged ahead of SMU in the two programs' all-time series, 37-36-7, when the Bears throttled the Mustangs 45-0 to start the 2014 season. ... SMU's 45-0 loss to Baylor last season spelled the beginning of the end for former SMU coach June Jones. Following the loss to the Bears, the Mustangs lost 43-6 versus North Texas and Jones resigned the next week. ... Baylor entered with its highest season-opening ranking in school history at No. 4.