In many ways coach Mike Smith’s decision Thursday night came down to cold, hard math.

The Falcons had the ball at the Saints’ 34-yard line trailing by four points. There was 2:28 to go and they had three timeouts.

What were the chances the Falcons would convert a fourth-and-15 and then score a touchdown? What were the odds Matt Bryant would make a 52-yard field goal, the defense would stop the Saints’ high-powered offense once again, and then the offense would drive for another field goal?

But beyond the probabilities, there were the circumstances. The Falcons were 2-8 and here was a chance to put the dagger in the Saints, their hated NFC South rival.

In the end, Smith played the percentages and lost. Bryant missed the field-goal attempt and the Saints ran all but five seconds off the clock to secure the 17-13 victory.

“There is not a whole lot of great fourth-and-fifteen plays,” Smith said. “We felt like a field goal and then get an opportunity on the plus side of two minutes with three timeouts, get an opportunity to get the ball back and a field goal wins the game.”

Converting a fourth-and-15 is a long shot in any circumstance. For the Falcons, the task was especially daunting because their pass protection had been shaky.

But the Falcons had gained 355 yards on 66 plays at that point (5.4 per snap) with 22 first downs. The defense had held the Saints’ high-powered offense to a field goal after halftime.

So the Falcons had an offense that had shown the ability to gain yards, a defense that was playing well and a kicker who’s usually reliable.

“I think in that situation we made the right choice,” Falcons tight end Tony Gonzalez said. “If we get those three points and we go out and stop them, now we’ve just got to kick a field goal which, the way our offense was moving the ball, we could definitely get in field-goal range. There was no doubt about that. But unfortunately we didn’t make the kick and that’s how it goes.”