Because he just can't wait to tackle somebody again.
''That would be the understatement of the century,'' Houston's star defensive end said. ''I explained it the other day it's like an animal in a cage.
''You rattle the cage and hope they unlock it, maybe the lock falls off, you hope somehow you're going to get out of the cage, and I think on Sunday they're finally going to open up the cage for me and I can't wait. I'm pretty hungry.''
Watt was healthy, but coach Bill O'Brien didn't think it was worth the risk for him to play even one snap in the preseason. That's given last year's Defensive Player of the Year plenty of time to sit back and think about what he'll do when he finally gets to play.
''I can't wait to play real football with this defense in a game in front of our home crowd,'' Watt said.
Watt leads a defense that added veteran nose tackle Vince Wilfork in the offseason and that should get a boost from the return of last year's top overall pick Jadeveon Clowney, who played just four games last season before season-ending microfracture surgery.
Watt was second in the NFL with 20 1/2 sacks in 2014 to become first player with two seasons with 20-plus sacks. He headlines a group of several star pass rushers in this game, which includes Chiefs linebacker Justin Houston, who led the league with 22 sacks last season. The Chiefs also have Tamba Hali, who has 79 1/2 sacks in nine seasons with the Chiefs.
''People who like pass rushing, they'll enjoy the game,'' Houston defensive coordinator Romeo Crennel said.
The work of Houston and Hali has even impressed Watt.
''They've been able to do some incredible things,'' he said. ''You do, you watch other pass rushers and you enjoy watching somebody at their craft excel. I just hope they don't excel that well on Sunday, that's all.''
While Watt raved about the Kansas City rushers, Chiefs coach Andy Reid discussed how difficult it is to deal with Watt because of the way the Texans move him up and down the line. Then Reid spoke of his time around Reggie White and how Watt reminds him of the Hall of Famer.
''I was lucky enough to be around Reggie White, who will probably go down as one of the all-time greats - you could put him anywhere,'' Reid said. ''J.J. has that same type of thing, he's not quite as big as Reggie was, but he's big enough. He's a good football player.''
Some things to know about the Chiefs-Texans game.
FILLING IN FOR FOSTER: Second-year player Alfred Blue is scheduled to start at running back in place of injured star Arian Foster, who is recovering from groin surgery. Blue, a sixth-round pick last season, had 310 total yards in three starts last season, highlighted by career-high 156 yards rushing against Cleveland. Houston also has running backs Chris Polk and Jonathan Grimes to help pick up the slack until Foster returns.
MACLIN'S DEBUT: Wide receiver Jeremy Maclin will make his debut for Kansas City on Sunday after spending the first five years of his career with the Eagles. He's impressed in preseason after leading the Eagles with a career-high 85 receptions for 1,318 yards receiving last season. Maclin is comfortable with Alex Smith and is eager to get going.
''I don't think I've been off to a better start with a particular quarterback,'' Maclin said. ''I trust him, he trusts me - we're able to get together and work on things we see on the football field.''
HOYER TAKES OVER: Quarterback Brian Hoyer will make his first start for Houston after beating out Ryan Mallett in camp. Hoyer started 13 games for the Browns last season and threw for a career-high 3,326 yards before signing with Houston in the offseason. O'Brien knows that some don't believe Hoyer is the answer at quarterback for a team that had to use four different quarterbacks last season because of injuries.
''I believe in him as a quarterback,'' O'Brien said. ''I believe in his knowledge of our system. I believe in his fit with what we're trying to do here. And now, of course, just like anybody else, he knows he has to go out there and do it.''
BERRY IS BACK: Kansas City safety Eric Berry will play a regular-season game for the first time since revealing he had lymphoma last November. Berry was declared cancer-free in June and cleared to practice just before camp.
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