Oklahoma may once again have analysts asking, “Can you really be one of the best college football teams in the country if you have one of the worst defenses?”

The Sooners won the Big 12 and reached the College Football Playoff last season, before losing to Alabama, 45-34. They did get the money against the Crimson Tide by covering a tall point spread of +14¹/₂. But, that was after falling behind 28-0 — in a game in which they allowed 528 total yards, 70 percent third-down conversions and the opposing quarterback completed 25 of 28 passes for 328 yards.

Sunday, Oklahoma starts its 2019 campaign at home against Houston in the only college football matchup of the day (ABC, 7:30 p.m.). Bettors trying to figure out whether Oklahoma deserves support as big favorites (3-7 ATS last year when laying double digits) or on the futures board (a top-six choice, but well behind perceived playoff shoe-ins Clemson and Alabama) should focus on defense.

Everyone knows coach Lincoln Riley’s offense is going to move the ball no matter who’s at quarterback. Will new defensive coordinator Alex Grinch (by way of Ohio State) be able to get results from a soft unit that passively watched opponents march up and down the field (while forcing just 12 turnovers in 14 up-tempo games)?

Houston’s offense should provide a stiff test, even in a game with such a high point spread. New Cougars head coach Dana Holgorsen (late of West Virginia) is an offensive guru. Plenty of talent returns from last season’s offense that lit up scoreboards before late-season injuries.

Here are the stats handicappers should watch:

Yards allowed per play: Because Oklahoma plays track meets, it’s going to allow a lot of yards per game. Opponents will be frantically trying to catch up. Even if OU’s defense turns out to be good, it will give some ground. Allowing 5.5 yards per play or fewer would put them in the upper half of the nation (the Sooners ranked 102nd last year at 6.13)

Yards allowed per pass: Oklahoma ranked a ridiculous 109th a year ago at 8.4. It needs to cut at least a yard off that average to be considered as chalk (Vegas slang for favorites) or as a threat to scare Alabama or Clemson in January.

Turnovers forced: The Sooners managed just six interceptions last year against opponents throwing 488 passes. And many opponents featured mediocre (or worse) quarterbacks in desperation mode. Three times that many should have hit defenders in the hands by accident.

Oklahoma will close as a hefty favorite at Sunday’s kickoff. It will be prohibitive favorites vs. most Big 12 foes. Early “game of the year” numbers this summer for marquee matchups suggested OU might be double-digit favorites over everyone but Texas, in the annual Red River Shootout in Dallas (OU settled at -3 quickly). The Sooners again will be a money burner for bettors unless the defense learns to gets stops in the last two quarters.