New England Patriots linebacker Bryan Cox vowed to seek justice on the field after a low block delivered by Denver guard Dan Neil broke his leg. The NFL delivered its own version of justice Thursday.

	Neil

The NFL fined Neil $15,000 for what it determined to be an illegal clip on Cox in the open field. A week ago, the league fined Denver tackle Matt Lepsis for rolling up on the back of Maa Tanuvasa's leg on a play in which the Chargers defensive lineman was lost for the season.

"Specifically, on a pass play, you clipped your opponent from behind and below the knee," NFL Director of Football Operations Gene Washington wrote to Neil.

According to NFL rules, no clipping from behind and below the waist against a non-runner is permitted. Clipping above the knees is legal in what is described as "close-line play." That is the area between the tackles and three yards on either side of the line of scrimmage.

Neil joins Lepsis and Cowboys tackle Flozell Adams as those fined for illegal blocks. Adams was fined for a chop block Aug. 30 in a game against Jacksonville.

Neil claimed he did not touch Cox on the play, but he told Broncos reporters that if he had touched Cox, the block would have been legal. His position didn't match with Washington's findings.

"Dan said he didn't touch him," Broncos coach Mike Shanahan said. "There's a few people that feel that there wasn't contact. There's a few people that feel that he got his back leg -- not his front leg that he broke, but his back ankle."

Also Thursday, the NFL fined Broncos linebacker Al Wilson $5,000 for hitting New England quarterback Tom Brady in the shoulder after a Patriots touchdown.

Like Neil, Wilson was not penalized during the game. In explaining its decision, the NFL said Wilson was guilty of unsportsmanlike conduct for hitting Brady as he attempted to congratulate a teammate.

John Clayton is a senior NFL writer for ESPN.com. Information from The Associated Press was used in this report.