Texans team doctor Walter Lowe said Williams underwent surgery in Dallas on Sunday to fuse and stabilize the cervical spine levels C-2 through C-4. Williams is expected to be able to walk again, but Lowe said the severity and depth of the injury makes it "highly unlikely that Harry will return to football."
Texans coach Gary Kubiak said, "The bottom line from my perspective is the surgery went well. Right now it's a rough day for him but everything went well."
A third-year pro who spent last season on the Texans practice squad, Williams had fought his way into the receivers picture this season. Kubiak said last week that Williams was the team's best special teams player.
"It's hard," Kubiak said. "In this business you root for kids."
"He was fixing to be as big part of this team and to go out there on that field and see this kid laying there after what he went through was tough. I think it's just the reality of how tough this game is and what can happen to you on any given play."
Kubiak said the episode had put things in perspective for him and his team.
"I just thank the good Lord the kid's going to be fine," he said. "I know it's a very, very difficult time. I talked to his mom. She's an amazing mom. He has a great support system, so Harry's going to be OK."
The players still seemed in shock Monday.
"Words can't explain how I feel," wide receiver Andre Johnson said. "Harry had shown up every day and was making plays for us. He was really a guy we could have counted on this season.
"We were talking about it this morning. You can be out there in one play and it can be over for you, just like that."
Williams is the second player in the past year the Texans have lost to a spinal injury. Defensive tackle Cedric Killings was injured in a headfirst collision with Indianapolis receiver Roy Hall in September, fracturing the C-4 vertebra.
"I talked to Cedric the other day and he told me how well he's doing," Kubiak said.
Like Williams, Killings was initially unable to move his hands or feet. But after surgery he recovered well enough to walk into practice later in the season.
Johnson looks forward to that day with Williams.
"We're rooting for him and I just can't wait to see him walk through those (practice) gates," he said.
The Texans signed fullback Jon Abbate on Sunday to take Williams' roster spot.
Notes: On Monday, the Texans placed fullback Jameel Cook on waivers. Cook was arrested last week after a Fort Bend County sheriff's deputy discovered marijuana in his car. ... Kubiak said the team would announce two more cuts Tuesday before the 3 p.m. deadline. ... RB Ahman Green, who is nursing an injured groin, worked out on Monday. Green is expected to be healthy for the regular season. But he and RB Chris Brown, who didn't practice Monday due to his back injury, are not expected to play in the last preseason game on Thursday against Tampa Bay.