Some NFL teams already are complaining about what can and cannot be challenged after watching Packers linebacker Clay Matthews' controversial hit on Vikings quarterback Kirk Cousins and Lions cornerback Tracy Walker's nullified interception of Jimmy Garoppolo last Sunday.

A few executives and coaches sounded off again this week, wondering why penalty calls, especially in the final two minutes of a game, are not reviewable.

The Lions were the victims of a holding penalty away from the play that cost them a potential game-winning interception. Lions defensive back Quandre Diggs was penalized for holding 49ers tight end George Kittle, which negated Walker's interception and cost the Lions a chance to put the finishing touches on a 17-point fourth-quarter comeback in a game they lost 30-27.

One executive bothered by the Matthews and Diggs calls said that 15-yard penalties in the final two minutes should automatically be reviewed.

Matthews was not fined for his much-discussed roughing the passer penalty following his hit on Cousins and also said he was not notified of any fine for his postgame comment that the penalty was a "terrible call."

Referee Tony Corrente ruled that Matthews "lifted [Cousins] and drove him into the ground" on the play, nullifying Packers defensive back Jaire Alexander's interception, which would have given Green Bay the ball with an eight-point lead. Instead, the Vikings drove 75 yards for the tying score in a 29-29 deadlock.

The day after the penalty, the NFL doubled down and said not only was it the correct call but that the hit would be included on a teaching tape sent to teams this week, along with a penalty from earlier in the same game on Vikings linebacker Eric Kendricks for hitting Aaron Rodgers.

Other teams also expressed surprise over Matthews' penalty. Washington coach Jay Gruden, whose team hosts the Packers on Sunday, said: "I don't know how that was a penalty." Rodgers also said he was surprised that Kendricks' hit was penalized. The linebacker was not fined.

ESPN's Rob Demovsky contributed to this report.