Detroit Lions defensive tackle Ndamukong Suh is facing discipline from the NFL for diving at the knees of an opposing player during Sunday's game against the Minnesota Vikings.

The controversial play occurred during an interception return by Lions linebacker DeAndre Levy, who scored an apparent touchdown to give Detroit the lead. But the play was nullified because Suh was whistled for an illegal low block against Vikings center John Sullivan well behind the play.

Ndamukong Suh has been flagged for controversial personal-foul penalties on multiple occasions over the past three seasons. AP Photo/Duane Burleson

Suh's block drew a 15-yard penalty and the attention of the league office. The two-time Pro Bowler said, however, that he was not attempting to injure Sullivan.

"I wasn't by any means going for his knees," Suh said after Detroit's 34-24 victory. "He knows that. We had a great conversation running out at halftime, and he understood. My aim was his waist to cut him off."

Sullivan said he was surprised that he didn't suffer a serious injury on the play. "That was bad," he said.

"I think guys get caught up in the play sometimes," Sullivan continued. "Sometimes things happen. It's hard to remember what you did when you get caught up in the moment. I appreciate the fact he came up and said something.

"It looked like it could have led to a pretty serious injury, so I feel like I'm pretty lucky today to be relatively unscathed."

Sullivan did not see Suh coming at him, he added.

"I missed the shot of it, but the guys were telling me about it," Vikings coach Leslie Frazier said. "Nobody thought that was a good play, and the fact they got a penalty because of it tells you it wasn't a good play. You hate to see guys go low on players. You've seen the results of it, so it's not a good thing when it happens."

Vikings defensive end Jared Allen also disapproved of Suh's low block.

"[Suh] is a good dude, but that's uncalled for," Allen said. "This is a fraternity. In the NFL, you try to take care of guys. Things happen, and guys are going to make hits. But you can't take a dude's legs out from behind on an interception return down the field.

"He plays hard. I like his style of play. But if you end a guy's career like that, it's just uncalled for."

The low block was not the first time that the 26-year-old Suh has been questioned for a controversial penalty. He was suspended two games in 2011 for stomping on the arm of Green Bay Packers offensive lineman Evan Dietrich-Smith during a Thanksgiving Day game.