IStock Photo 4267274 © Brandon Laufenberg

On Sunday, February 1, 2009, right before halftime in Super Bowl XLIII, Pittsburgh Steelers linebacker James Harrison made NFL history when he intercepted a pass from Arizona Cardinals quarterback Kurt Warner.

Harrison stole Warner’s pass and ran it for 100 yards into the end zone—the longest interception in Super Bowl history (It broke the previous Super Bowl record set by Seattle Seahawks Kelly Herndon, who ran for 76 yards in Super Bowl XL, three years earlier). Steelers defensive coordinator Dick LeBeau was quoted in an article on NFL.com as saying, “I’ve said, and I believe it, it’s the greatest single defensive play in Super Bowl history.”

Harrison’s interception not only came in a critical football game, but it also defied the norm. Although the odds an NFL pass will be completed are 1 in 1.67 (60%), the odds such a pass will be intercepted are 1 in 31.52.

So, how do some of the NFL’s most talented active quarterbacks stack up against the odds? New England Patriots’ Tom Brady has an interception rate of 2.3 percent, according to sports author Larry Canale, writing in a New York Times blog, The Fifth Down. Indianapolis Colts’ Peyton Manning is intercepted 2.8 percent of the time. Brett Favre, another sure Hall of Famer, has thrown for more yards, completed more passes, and thrown more touchdowns than any quarterback in NFL history. Of his 9,280 passes, he’s been intercepted 310 times. That’s 3.3 percent, or approximately 1 interception out of every 30 passes.

Compared to the game’s all-time great quarterbacks, Favre fares well. Troy Aikman was intercepted 141 times (every 33 passes); George Blanda was intercepted every 14 passes; Terry Bradshaw every 19 passes. According to Canale, Favre “has been less prone to interceptions than all but five Hall of Fame quarterbacks.”

Of course, it’s not always the quarterback’s fault that a pass is intercepted. Some defenders are better at intercepting passes—and thereby raising a quarterback’s odds of throwing an interception—than others. Who is this year’s biggest odds spoiler? Darren Sharper of the New Orleans Saints, who racked up a league-leading 7 interceptions in the first 9 weeks of the 2009 season, and leads all active players in career interceptions.