But what sets apart the great players is an ability to manage pressure, the psychiatrist added.
"They approach the games thinking, 'This is what I was meant to do, to play the biggest games,'" he said. "I think [Flacco] and his teammates are going to embrace this pressure and channel it into a focused performance."
This is Flacco's second time on the SI cover; the Sept. 19, 2011, issue featured a photo of him having handed off the ball to a charging Ray Rice. The headline: "Baltimore thumps the Steelers. Any questions? Raven Strong."
Well, one question does comes to mind: How did the Ravens do in their next game?
C. Shane Reese, a statistics professor at Brigham Young University — where, coincidentally, he once taught Ravens tight end Dennis Pitta — thinks the SI effect is more likely a manifestation of that old adage: What goes up must eventually come down.
Or, as statisticians call it, "regression to the mean," he said. Whatever a player or team's level of play, they likely have exceeded it to get on the SI cover, and what seems like a jinx is really just the natural reversion to their normal abilities, Reese said.
"It's akin to what people call the sophomore slump," said Reese, who chairs the sports section of the American Statistical Association. "They had a great season; when they're on the cover, they're at the tail end of it."
It is even harder to convince statisticians of the so-called "Madden NFL" curse, in which players featured on the cover of annual editions of the video game went on to suffer injuries and other problems. Ray Lewis, on the cover of "Madden 2005," had his first season without an interception and missed the final game of the season with an injured wrist.
But Reese said that too few players have been on a "Madden" cover — the game began featuring one a year in 1999 — to discern any pattern.
"The problem of a small sample size," he said, "is notorious in statistics."
Glickman, the Boston statistician, said Ravens fans need not fear the curse. If he were trying to predict the outcome of Sunday's game, he would look at more conventional statistics — previous match-ups, each team's regular-season results, recent trajectories, which players are injured and a host of other factors.
But even that wouldn't be able to capture the complexity of factors that will figure into the game, he said.
"It's very hard to come up with something comprehensive enough," Glickman said of trying to predict game outcomes. "The Ravens beating the Broncos — no one thought that would happen."