Next Level: Tulane quarterback Jordy Joseph

If you’re looking for the closest parallel to the odds Tulane quarterback Jordy Joseph will have to overcome against Memphis on Saturday, try to remember Richard Irvin in 2004.

Irvin, then an unknown redshirt freshman from California, made his first start at TCU in the Green Wave’s road finale. Subbing for injured starter Lester Ricard, he threw five touchdown passes, including the game-decider with 43 seconds left, as Tulane (a 13-point underdog) won 35-31.

The comparison breaks down from there. Although TCU had gone 11-2 a year earlier, the loss to Tulane dropped the Horned Frogs to 5-6 in what would be their only sub-.500 season in a 14-year span.

Memphis (7-0) is chasing a second consecutive American Athletic Conference championship and maybe a spot in the College Football Playoff if it wins out.

Joseph, a fifth-year senior and walk-on who had thrown one career pass until mopping up against Houston on Oct. 16, just needs to enjoy the experience. Tulane was a 32-point underdog as of Thursday.

“As a team, we don’t think about it,” he said. “It’s almost like a faceless opponent. The bottom line is, if we don’t go out and execute, we can’t beat anyone.”

Joseph, unlike Irvin, is a walk-on. While Irvin was 6-foot-2 — standard height for a college quarterback — Joseph is 5-10.

Memphis averages more points (48.9) than TCU scored in any game in 2004. But Joseph does have three years of experience over Irvin.

“He’s confident,” coach Curtis Johnson said. “He can get us in and out of plays. We just have to lift him up and keep going with him. I think he’s going to be great.”

Joseph and Irvin have one more similarity: their intelligence. Joseph was valedictorian at New Iberia High in 2010. Irvin, who started one more game at Tulane (a 55-7 loss to Louisville), transferred to Harvard, where he played sparingly for two years.

Four Downs

1. End of the gauntlet

Tulane’s last four games in October always appeared tough, but no one could have foreseen how brutal it would turn out to be. Navy, which had its only loss in a close game at Notre Dame, qualifies as the weak link. The others — Temple, Houston and Memphis — are among the 14 unbeaten teams in college football. Regardless of what happens Saturday, the Wave will be happy to get to November.

2. Height disparity

Seriously, has there ever been a bigger differential between quarterbacks than Tulane’s Jordy Joseph (5-foot-10) and Memphis’ Paxton Lynch (6-7)? Joseph, filling in for the injured Tanner Lee, has to hope for better results than the Wave’s last emergency replacement: D.J. Ponder in 2011. Ponder went

14-of-39 with two interceptions in a 41-13 loss to Louisiana-Lafayette.

3. Keeping the faith

A Tulane victory would be one of the biggest upsets in recent history. The key is playing with pride, trusting a talented defensive front seven to keep Memphis’ offense in check and going hard for four quarters. If the Wave gives the same effort it showed at Navy, coach Curtis Johnson won’t have to work to keep his players’ motivation level high for the stretch of winnable games in November.

4. Blocking Well

Tulane’s previous three opponents rank 1-2-3 in the AAC in total defense. Memphis is ninth. Lee has to be kicking himself that he won’t be able to take shots at the Tigers’ vulnerable secondary, but even with Joseph, the Wave should have more room to operate. The offensive line needs to give him time and open holes, keeping Lynch off the field as much as possible.