HOUSTON -- When the Houston Texans' coaching staff announced to the linemen that they would be running one-on-one blocking drills during minicamp last May, the rumbling started immediately, players say.
The NFL's rules about minicamp are spelled out in the collective bargaining agreement with the NFL Players Association: no contact, no pads.
"There's a reason why these drills are prohibited in the offseason," offensive guard Dan Stevenson said. "Football is dangerous enough as it is."
But several sources told ESPN that even after the team's player representatives complained to head coach Gary Kubiak, the drills continued; and by the end of minicamp, three players had suffered season-ending injuries.
According to four players and a member of the team's front office who spoke on the condition of anonymity, Kubiak and his coaching staff conducted the drills despite the fact that players were not wearing pads. Their only protection, they said, was helmets.
"It was a live blocking drill. There were people getting pancaked. Everyone's going as hard as he can," Stevenson said.
Stevenson suffered a labrum tear in his right shoulder that he believes might end his career.
"I was the third offensive lineman who was done for the season, just from that drill," offensive tackle Jordan Black said. "If nobody's going to stand up, it's just going to continue."
Black had surgery to repair a torn labrum, was released by the team in June and has since signed with the Jacksonville Jaguars. Chukky Okobi suffered a triceps injury, and has not signed with a new club.
"I felt like, for my career, my occupation, my dreams, for all this to be taken away from me, to be jeopardized not for just one season but for my entire football career for something that wasn't supposed to be done -- I was upset," Stevenson said.
Okobi couldn't be reached for comment. Black and Stevenson said that although they accept football's injury risks, they are distressed that their seasons ended in a drill they say should not have taken place.
Stevenson and Black have labor grievances pending against the team, and Stevenson plans to sue the Texans.
Asked about the players' charges, team counsel Suzie Thomas wrote in an e-mail: "I am unable to comment, other than to say that information set forth ... is inaccurate."
Kubiak did not return calls to his office at Reliant Stadium.
NFL and NFLPA officials said there is no specific punishment defined for a team that holds prohibited drills during a minicamp. An NFL spokesman said grievances have been filed in relation to the minicamp drills and the league will look into the players' allegations as part of that process.
Stevenson's current grievance is a "non-injury" complaint that relates to the minicamp drill. A previous injury grievance was denied by the NFL Management Council. In that rejection, the NFLMC cited numerous procedural problems with Stevenson's complaint.
One portion of the rejection letter, Stevenson said, read, "the Texans deny ... that 'players were required to participate in drills which are explicitly prohibited.'"
Once the team denied that the drill had taken place, Stevenson took a video camera into the Texans' meeting room and filmed the team's video of the workout. The video, which was provided to ESPN, shows what appear to be full-speed, full-contact drills.
Black and former Texans lineman Fred Weary also signed notarized affidavits supporting Stevenson's description of what took place during minicamp, from the complaints of the player representatives to Stevenson's shoulder injury.
The players said it is not uncommon for coaches on many teams to schedule such drills during minicamp, but it is unusual for coaches to proceed with the drills when players object.
Tom DePaso, associate general counsel for the NFLPA, said the union often hears complaints about offseason drills that violate the CBA.
"It's this classic thing in the offseason. Coaches really want to get started on the new season, and on the other hand, we need our guys to learn and they need to rest," DePaso said.
DePaso wouldn't specifically address the grievances against the Texans or the three players who suffered season-ending injuries.
"If that were the case," he said, "that would be extraordinary."
T. J. Quinn is an investigative reporter for ESPN. He can be reached at email@example.com.