ESPN Analyst Rips Mavs' Defense: 'They Don't Play Hard Enough!

He also pointed to the team's defensive woes as being the potential difference maker between a deep playoff run or getting bounced in the play-in or first round.  

"They don't lay it on the line defensively the way you have to to be considered a legitimate contender," Legler said on First Take. "They have everything you need offensively every single night to go toe-to-toe with any team in this league...They don't compete on the defensive end of the floor to the extent that you need to."

Legler later added: "If they can just leave a little skin on the floor, they have an opportunity to truly challenge to get to the Western Conference Finals if they do it. If they don't, they go home early, and it's just a bunch of gaudy numbers that guys are putting up every night that doesn't mean anything." 

For as good as the offense has been for most of the season, Dallas' defense has been equally as bad, even outside of allowing an average of 127.5 points per game in its last five games. The Mavs are 24th in points allowed per game (118) and 22nd in defensive rating (117.6).

Dallas looked like a completely different team during its seven-game winning streak when it allowed just 105.43 points per game, and an opposing team only scored over 110 points against them twice in that stretch. That level of defense with Luke Doncic and Kyrie Irving will make Dallas one of the most dangerous teams in a loaded Western Conference. 

If the Mavs are going to remain a threat if they make the playoffs, that's the defense they need to play nightly. And if the Mavs can't regain that form on defense, Legler's prediction of a quick exit may come to fruition, and decisions will need to be made about the direction of the franchise and how they can fix what's holding them back.