On the final play of Super Bowl XLVII, Ted Ginn had an opportunity to return a free kick (following an intentional safety by the Ravens) to give the 49ers a walk-off win. But he was tackled by the Ravens, and Baltimore won.
In the event that Ginn did break a long return, though, Joe Flacco was on the sideline preparing his teammates not in the game to tackle Ginn.
"If he starts to break it, go tackle him," Flacco was heard yelling at teammates on NFL Network's Sound FX.
"I don't know, I mean what else -- they might be able to give him a touchdown on that, but I don't know," Flacco said when asked if they should really do that.
"Hey, if he breaks it," Flacco continued yelling while walking down the sideline. "If he busts it for some reason, go tackle him. I don't know the ruling on that, but ..."
Um, but nothing. Tackling Ginn would've been a terrible idea, unless he was at the 1-yard line, and even then it wouldn't have mattered.
According to the official NFL Rulebook, this would qualify as a "Palpably Unfair Act" (Rule 12, Section3, Article 3) and it would allow, as you can see below (emphasis mine in the second section) the refs to "award a score."
Article 3: Palpably Unfair Act. A player or substitute shall not interfere with play by any act which is palpably unfair.
Penalty: For a palpably unfair act: Offender may be disqualified. The Referee, after consulting his crew, enforces any such distance penalty as they consider equitable and irrespective of any other specified code penalty. The Referee may award a score. See 15-1-6.
In other words, if, say, Matt Birk or Ray Rice came charging out on the field and tackled Ginn as he was streaking down the sideline, the refs could award the 49ers a touchdown if it was obvious that Ginn was going to score or if he was in the open field all alone. Or, heck, even if he was running into a pair of Ravens positioned at the goal line.