ALLEN PARK, Mich. -- The NFL has decided not to fine Detroit Lions defensive tackle A'Shawn Robinson for his unnecessary roughness penalty against Dallas on Monday night, according to a source.

Robinson was flagged in the third quarter. It appeared as if he lifted Cowboys running back Ezekiel Elliott off the ground to tackle him.

Lions coach Jim Caldwell said multiple times this week that he did not believe what Robinson did was a penalty, and that he would not teach him to tackle any differently.

"The same answer I gave you [Monday] night when I saw it, saw it happen out there, and I didn't think it was a penalty," Caldwell said Tuesday. "I don't think it's a penalty today. But like I said, we have mechanisms to go about that, to talk about it, to make certain the league hears how we feel about those certain things.

"We like to tend to that protocol rather than complain about things.... That borders in on starting to worm in on excuse-making, which I don't want to have any part of."

A'Shawn Robinson's tackle of Ezekiel Elliott in the third quarter drew an unnecessary roughness penalty Monday night. AP Photo/Michael Ainsworth

Caldwell often instructs his players not to get into it with officials about potentially bad calls. When those things have happened this season, his players typically have asked for explanations and then gone about their business on the next play.

"I think that's the right thing to do," Caldwell said Friday. "You can cry and bellyache and complain and whine, all of the things that keep you losing. You can do all of that stuff if you want to. I believe we have little time for that.

"You better start thinking about the next play or the next game, or whatever it might be, and it'll serve you well. Let's control the things that we can control."