3 Cowboys nightmares that were unearthed in ugly loss vs Cardinals

2. Susceptibility to penalties

The Cowboys were so dominant in the first two games that fans potentially forgot what it felt like to watch sloppy football. Newsflash: it's still chest-pain-inducing.

You can't play perfect all the time, but Dallas was on the wrong side of history with how much laundry they drew in the first half.

According to Michael Gehlken of the Dallas Morning News, the Cowboys' 10 accepted penalties in the opening 30 minutes was tied for the most by an NFL team since the 49ers had 11 against the Lions 12 years ago in 2011.

Things didn't get much better in the second half, as linebacker Drew Harper was called for a holding penalty that negated KaVotae Turpin's 51-yard punt return. It was a 61-yard penalty in the grand scheme.

For the game, Dallas committed 13 penalties for 107 yards. They had 10 penalties combined against the Giants and Jets. It's not time to hit the panic button, but undisciplined football was a big talking point early in Mike McCarthy's Cowboys tenure.

Teams are seldom going to play perfect ball, but contenders aren't supposed to allow the mental errors to snowball like they did on Sunday.