Trying to snap a two-game losing skid, the Steelers flew to the Edward Jones Dome for a Week 16 Thursday night interconference duel with the St. Louis Rams.  In the first quarter, Pittsburgh smashed first as QB Ben Roethlisberger completed a 17-yard TD pass to WR Nate Washington.  The Rams would respond with QB Marc Bulger completing a 12-yard TD pass to RB Steven Jackson.  In the second quarter, the Steelers regained the lead with kicker Jeff Reed getting a 21-yard field goal.  However, St. Louis took the lead with Bulger completing a 12-yard TD pass to WR Isaac Bruce.  Afterwards, Pittsburgh got the lead again as Roethlisberger completed a 33-yard TD pass to Washington and a 12-yard TD pass to RB Najeh Davenport.  The Rams end the half with kicker Jeff Wilkins getting a 52-yard field goal. In the third quarter, the Steelers increased their lead with Davenport getting a 1-yard TD run.  St. Louis would respond with Bulger completing a 23-yard TD pass to WR Drew Bennett.  In the fourth quarter, Pittsburgh ended the game with Reed nailing a 29-yard field goal and CB Ike Taylor returning an interception 51&#160;yards for a touchdown. With the win, the Steelers improved to 10-5. The Cleveland Browns' loss three days later automatically clinched the Steelers' first AFC North title since 2004. WR Hines Ward (6 receptions for 59&#160;yards) surpassed John Stallworth as the all-time franchise leader in career reception yards with 8,726&#160;yards.  Also, Santonio Holmes got a career-high with his game-best 133 receiving yards on 4 catches. Finally, Ben Roethlisberger got his third career "perfect" game (16/20 for 261&#160;yards and 3 touchdowns). RB Willie Parker (1 carry for &#8722;1&#160;yard) got injured on Pittsburgh's second offensive play of the game after getting tackled by LB Will Witherspoon.  He would suffer a fractured right fibula, effectively ending his season.
Question: How many "perfect" games did Roethlisberger get in his career?
Answer: 3