A little over nine months ago, four-time All-Pro defensive end J.J. Watt struggled to lift his leg after surgery.

After fracturing his tibial plateau on the first drive of the Texans Week 5 game against Kansas City, Watt's 2017 was cut short for a second year in a row. He slowly began his rehabilitation, wondering if a return from such a gruesome injury, could even be possible.

"For the first two months of this one, I wasn't allowed to walk," Watt said Thursday. "You're sitting there on your couch and you're like, 'How the hell am I going to get back to where I need to be?' You're sitting there and you can't even do a leg raise, you can't even do anything and you're like, 'Is this possible?' Then you just take it one day at a time, step-by-step.

Watt described the process of slowly regaining strength in his leg, from lifting it to adding weight to eventually walking and running. The three-time AP Defensive Player of the Year worked his way back and was cleared for training camp.

On Thursday, Watt participated in team drills for the first time since his surgery.

"Came back in great shape," head coach Bill O'Brien said. "He's worked really hard. I mean, he's better to ask about it than me but he's worked extremely hard to get back to where he's at. He's a driven guy, as we all know. He's a great leader on this team and we're glad to have him back."

While he won't make any proclamations about his recovery or predict sack totals just yet, Watt is excited about his return this time around.

"I think I'm starting in a really good place this year," Watt said. "It feels like I'm starting just a regular training camp, which is good. I feel like I'm starting fresh, which is the goal. When I started this rehab process, the one thing I wanted to do was earn a clean slate. I wanted to earn a fresh start, earn a chance to go out there, start a training camp from day one, go out there and play. I think that clean slate has come and I have a chance to once again try to write my own story."

The Texans kicked off training camp on Thursday at The Greenbrier in White Sulphur Springs, W. Va. for the second year in a row. Training camp will return to Houston following the Texans' first preseason game at the Kansas City Chiefs on Aug. 9.