The first snap of the all-new Alliance of American Football league, or AAF, is just around the corner. The San Antonio Commanders host the San Diego Fleet at the Alamodome on Saturday at 8 p.m. ET. It's the opening game of the league's 10-week, 40-game regular-season and you can watch it on CBS. The latest Commanders vs. Fleet odds have the Commanders favored by two, while the over-under, or total points Vegas thinks will be scored, is 50.5. There are plenty of unknowns for the first set of games for an all-new pro football league, so before you lock in your Commanders vs. Fleet picks for the inaugural week of Alliance of American Football games, check out what SportsLine pro football expert Mike Tierney has to say.

A renowned sportswriter whose work appears in the New York Times and Los Angeles Times, Tierney has reported from seven Super Bowls. He's intimately familiar with all levels of the game and knows every coach's philosophy and approach to devising game plans.

Tierney was all over the Patriots in the 2019 Super Bowl, enabling him to finish the 2018 NFL season with a sparkling 63-46 record against the spread. Anyone who has followed him is way, way up.

Now, with the new league set to kick off Saturday, Tierney has evaluated Commanders vs. Fleet from every possible angle and locked in his AAF picks. We can tell you he's leaning toward the over, but his much stronger play is against the spread. You can only see that pick over at SportsLine.

Tierney knows that San Diego head coach Mike Martz will employ a pass-happy offensive attack. Fleet quarterback Mike Bercovici played in a pass-first offense at Arizona State, where he finished his senior season with over 3,800 passing yards, 30 touchdowns and just nine interceptions. He also recorded six rushing scores in his final season at ASU.

The Fleet also feature an explosive running back who can take over a game. Ja'Quan Gardner finished his career at Humboldt State with 5,495 rushing yards and 72 touchdowns. He averaged over 130 yards per game and more than 6 yards per rush during his four-year career.

But just because the Fleet feature a number of play-makers on the offensive side of the ball doesn't mean they'll be able to stay within the AAF spread against San Antonio.

The Commanders' offense will be led by former Cowboys third-string quarterback Dustin Vaughan. The 6-5 signal caller dominated at West Texas A&M in his final season, throwing for 5,401 yards and 53 touchdowns.

Alongside Vaughan in the backfield will be running back David Cobb, a former fifth-round pick of the Tennessee Titans. Cobb is tough to bring down, which was extremely apparent while he was at the University of Minnesota. Cobb proved to be a downhill runner, rushing for 2,831 yards and 20 touchdowns in his last two seasons with the Golden Gophers. The Commanders will look to get Cobb going early and often, which will lead to an effective play-action passing game against San Diego on Saturday.

Tierney has dissected this matchup and unearthed a major x-factor that makes one side of the spread a must-back. He's only sharing what it is, and who to back, at SportsLine.

Who wins Commanders vs. Fleet? And what major x-factor makes one side of the spread a must-back? Visit SportsLine now to see which side you need to jump all over Saturday, all from the incomparable expert who just racked up another big cash in the Super Bowl.