If we were still in the Bowl Championship Series era, then it would be acceptable for No. 6 Auburn to lose its season opener to a good Louisville team, with the schools squaring off Saturday in Atlanta.

As long as you won the SEC title, you were pretty much assured of playing in the BCS title game.

However, we are in the College Football Playoff era, and it’s somewhat difficult to imagine a two-loss team getting in.

Already one Power 5 conference team has to be left out. Then you have teams like Notre Dame, BYU and Boise State who are capable of snagging one of those four spots in 2015  — the Cougars or Broncos would have to go unbeaten to be in the discussion and only one can since they play each other.

Auburn is a very talented team, but can it really win out against the crazy-hard SEC slate? I doubt it. So a win is necessary on Saturday.

Here’s a look at five Louisville players whom Tigers fans should keep an eye on for Saturday’s game. Auburn is a 10.5-point favorite. The schools have met just once previously: a 16-3 Auburn win in 1974.

QB Reggie Bonnafon: Cardinals coach Bobby Petrino, one of the best offensive minds in the business, is playing  mind games with Auburn defensive coordinator Will Muschamp. Petrino has four co-starters at quarterback on his depth chart before Saturday’s opener: Reggie Bonnafon or Kyle Bolin or Will Gardner or Lamar Jackson. Petrino knows who will start but sees no point on alerting Auburn to that fact before the game. And why should he? The vast majority of media following the program think it will be Bonnafon. He played well at times (not so much at others) as a true freshman a season ago, completing 50.8 percent for 864  yards, five TDs and four picks. He also rushed for 164 yards and five TDs. Bonnafon seemed to get a leg up on former starter Gardner this spring as Gardner was rehabbing an ACL tear that ended his 2014 season in November.

RB Brandon Radcliff: Last year as a redshirt sophomore, Radcliff was the team’s rushing leader with 737 yards and 12 touchdowns while averaging 5.1 yards per carry. The 5-foot-9, 214-pound Radcliff patterns his game after Seattle Seahawks star Marshawn Lynch. That power ability showed last year on third downs. Radcliff moved the chains on 13 of his 18 carries, seventh-best of any Power 5 back. Just nine of his 144 carries (6.2 percent) ended in a loss, which was the third-best rate in the ACC.

WR James Quick: Louisville has to fill the very big shoes of receiver DeVante Parker, a 2015 first-round pick of the Miami Dolphins. Despite missing a handful of games last year, Parker still had 43 catches for 855 yards and five scores. Quick, a former high school sprint champion, has the most game experience of any returning Louisville receiver. Quick was second or third on the team in most receiving categories last year after recording 36 catches for 566 yards and three touchdowns. No other returning receiver had more than seven catches.

DE Sheldon Rankins: The senior was named to the 2015 preseason All-ACC first team. In 2014, Rankins started every game, recording 53 tackles and team-highs with 8.0 sacks and 13.5 tackles for loss. He also added two interceptions. He was voted a third-team All-ACC selection by the coaches and media. Rankins, who also played some tackle, pondered going pro.

LB James Burgess: The senior from Florida is a three-year starter and also was a 2015 preseason All-ACC first-team pick. Last year, Burgess finished third on the team with 71 tackles, while adding 10 tackles for loss, three sacks and three interceptions. The Louisville defense has lost six starters from a unit that finished 2014 ranked sixth nationally in total defense so Burgess will be the clear heart-and-soul in 2015. “I really believe this defense is going to be better this year,” said Burgess to the Louisville media. “I believe we’re going to be number one in the country.”