Starts this weekend.

Some things you should know if you are going to wager on it:

There will be no television timeouts and fewer full-screen commercial breaks.

35-second play clock

No extra points. Every touchdown will be followed by a two-point conversion attempt.

No kickoffs. Each team starts a possession after a score or at the start of a half at their 25-yard line

Instead of onside kicks, which are not allowed, teams will attempt the equivalent of a fourth-and-12 play from their 28-yard line. A conversion means it keeps the ball.

These will only be allowed when a team is trailing by at least 17 points or for either team in the last five minutes of a game.

There will be a ninth member of the officiating crew called a “SkyJudge,” who will sit in the press box and “use real-time technology to correct clear errors involving player safety anytime during a game, and pass interference inside of five minutes left in the fourth quarter.

Coaches are allowed two challenges but cannot challenge a call in the last two minutes of either half or in overtime (challenges are automatic in those timeframes).

Overtime

Each team will get the ball only once, first and goal from the 10, and they have to score a touchdown and go for two. Games can end in a tie.

Atlanta Legends

Coach: Kevin Coyle, a longtime NFL assistant who originally signed on to be the Legends' defensive coordinator but was promoted to head coach in January after former Minnesota Vikings coach Brad Childress stepped down. Former NFL quarterback Michael Vick will make his coaching debut as Atlanta’s offensive coordinator.

Top players: Denard Robinson, a quarterback sensation at Michigan earlier this decade, is listed as a running back for the Legends (he last played in the NFL for the Jaguars in 2016). Aaron Murray, the SEC’s all-time leader in touchdown passes, will start at quarterback.

Birmingham Iron

Coach: Tim Lewis, a longtime NFL assistant who was defensive coordinator of the Giants and Steelers earlier this century.

Top Players: Running back Trent Richardson, the No. 3 overall pick of the 2012 NFL draft who’s mostly been out of football since 2014, returns to Alabama to revive his career. Former Auburn cornerback Chris Davis, of “Kick Six” fame, also is on the roster.

Memphis Express

Coach: Mike Singletary, NFL Hall of Famer and former head coach of the San Francisco 49ers.

Top players: Former Titans quarterback Zach Mettenberger and former NFL second-round pick Christian Hackenberg are battling to become the Express’s starting quarterback (Hackenberg reportedly has the edge).

Orlando Apollos

Coach: Steve Spurrier.

Top players: Will Hill, who started 32 NFL games earlier this decade before his career was sidetracked by substance-abuse problems, returns to the field, as does wide receiver Charles Johnson (60 receptions for the Vikings from 2014 to 2016).

Arizona Hotshots

Coach: Rick Neuheisel, the former coach at Colorado, Washington and UCLA who has spent the last few years as a sports broadcaster.

Top players: Former Oklahoma and Texas A&M standout Trevor Knight will play quarterback for the AAF favorites, while linebacker Scooby Wright (ninth in the 2014 Heisman Trophy voting) will anchor the defense. NFL veteran Nick Folk will handle field goals.

Salt Lake Stallions

Coach: Dennis Erickson, who’s served as a head coach for six NCAA programs and two NFL teams.

Top players: Matt Asiata, who led the Vikings in rushing in 2014, is one of the Stallions' running backs. Defensive tackle Sealver Siliga started for the Patriots in Super Bowl XLIX in 2015 and had four tackles.

San Antonio Commanders

Coach: Former Oregon State, Nebraska and San Diego Chargers coach Mike Riley will lead the Commanders.

Top players: Greg Ward Jr. threw 52 career touchdown passes as a quarterback at Houston from 2013 to 2016, but he’ll be playing wide receiver for the Commanders. Linebacker Jayrone Elliott played in 38 games for the Packers between 2014 and 2016, registering four sacks.

San Diego Fleet

Coach: Mike Martz, who coached the Rams from 2000 to 2005 and led St. Louis to the Super Bowl in 2002, returns to the sideline for the first time since 2011.

Top players: Perhaps the most recognizable name on the Fleet’s roster is quarterback Mike Bercovici, who threw for 3,854 yards and 30 touchdowns for Arizona State in 2015.