PITTSBURGH (AP) - Ryan Shazier let Buffalo Bills tight end Scott Chandler sprint by him before the rookie Pittsburgh Steelers linebacker gave chase.
The moment Chandler appeared to be open down the seam, EJ Manuel lofted a pretty spiral in Chandler's direction.
It looked like the right decision. It wasn't.
Shazier needed all of two steps to close the gap on Chandler. One well-timed leap and the 15th pick in May's draft had the ball in his hands. By the time he was finally tackled more than 25 yards downfield, the Steelers were in Buffalo territory - and any concerns about Shazier's banged-up right knee were long forgotten.
So much for that ''boo boo'' coach Mike Tomlin kept talking about.
In the span of a precocious half during Pittsburgh's 19-16 win Saturday night, Shazier did more than make up for the week he lost while nursing his knee back to health. He offered proof he's ready to handle his role in what the Steelers hope is a defensive revival in 2014.
Shazier's first game in an NFL uniform included 11 tackles, his graceful interception and a post-play collision that accidentally sent Buffalo rookie wide receiver Sammy Watkins to the trainer's room with bruised ribs.
''I think it's a great confidence booster,'' Steelers safety Troy Polamalu said.
While Tomlin tried to tamp down any concerns about Shazier's knee, the former Ohio State star concedes he was more than a little concerned after he felt a twinge while tackling teammate Le'Veon Bell during practice earlier this month.
''But everything happens for a reason,'' Shazier said.
Shazier missed Pittsburgh's preseason opener against the New York Giants and wasn't cleared for full contact until 48 hours before facing the Bills. As impressive as he was Saturday, he insists he's still not quite himself.
''I just got back to practice two days ago,'' he said. ''I don't feel you can be 100 percent with that amount of practice.''
Consider it a warning. Lining up alongside Lawrence Timmons, Shazier was as relentless as advertised. Racing sideline to sideline - often blowing by Timmons on his way to the ball - Shazier's No. 50 was a black and gold blur at times.
On Buffalo's second play from scrimmage, he tackled running back Fred Jackson. On the next down, he pulled Chandler to the turf. A little while later, he chased Manuel out of bounds after a short gain.
It was just the beginning. On special teams, Shazier smashed into kick returner T.J. Graham short of the Bills 20. The ensuing drive ended with Shazier's interception, and on the next kickoff, Shazier dragged Graham to the turf yet again.
The first quarter wasn't even over. So much for jitters.
''I wouldn't be surprised if they were testing me,'' Shazier said. ''But I did what I had to do.''
Still, he wasn't quite perfect. Shazier slipped trying to tackle Chandler near midfield early in the second quarter. Chandler picked up 24 yards on the third-and-27 from the Pittsburgh 35, giving kicker Dan Carpenter enough room for a 53-yard field goal.
It's that play perhaps more than the others that will stick with Shazier.
''I feel like you have to check yourself every day,'' he said. ''The game will humble you.''
Just in case it doesn't, Shazier's teammates will fill the void for a franchise that considers defensive excellence a requirement. As easy as he made it look at times, he is well aware he's just one very raw cog in a machine that's looking to return to form after a subpar 2013.
''I feel like it was still a difficult defense, still a lot of complicated things in it,'' Shazier said. ''But I feel like I have a lot of great guys around me, helping me learn.''
The education will continue Thursday when the Steelers travel across the state to face Philadelphia. An encore might be difficult. That's fine. Even at age 21, he understands games like the one he enjoyed Saturday don't come around often.
''One week I might have 11 tackles; one week I might have five,'' he said. ''I'm just doing whatever they want me to do.''
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