Fourth down? Safety first

Late in the first half of the AFC championship game, Indianapolis Coach Tony Dungy made a fourth-down decision that may have won the game for the Colts.

Trailing, 21-3, Indianapolis’ longest drive of the first half stalled at New England’s eight-yard line with 11 seconds remaining. Although quarterback Peyton Manning and the RCA Dome crowd wanted the Colts to go for a touchdown, Dungy thought otherwise and opted for a field goal.

Dungy’s fourth-down choice proved to be the right one when the Colts scored 32 points in the second half to rally for a 38-34 victory.

Actually, his decision was not much of a surprise considering the lack of success his teams have had on fourth down during his 11-year NFL career as a head coach.

Dungy, who averages less than one fourth-down gamble a game, has an overall success rate of 48.3% -- 84 for 174 -- when he decides not to kick on fourth down. However, that number drops to 25% -- five for 20 -- in the postseason.

This season, Dungy attempted fewer fourth-down gambles than any coach in the NFL -- and had the least success, 0 for 4. In their three playoff games, the Colts’ only fourth-down attempt wasn’t planned: It came on a botched punt by Hunter Smith against Kansas City.

In 2001, NFL coaches went for it on fourth down an average of 15.1 times a season. This season the average was 14.7, up from 14.5 a year ago.

When it comes to taking chances on fourth down, Chicago Coach Lovie Smith isn’t as cautious as Dungy, but he’s still on the conservative side. The Bears were under the league average with 13 fourth-down attempts, converting nine for an 69.2% rating that was fourth-best in the league.

Smith’s success rate on fourth downs in the postseason separates him from Dungy. Over the last two years, the Bears have converted 80% -- four of five -- of their fourth-down attempts, including all three this season.

The key to that success has been Chicago’s running game.

Including the playoffs, the Bears are 10 for 11 when they needed two yards or less, running for first downs or touchdowns nine times. In Chicago’s 39-14 victory over New Orleans in the NFC championship game, the Bears twice converted fourth-and-short situations with power running plays.

In contrast, two of the Colts’ failed fourth-down plays this season -- one a run -- were with two yards or less to go.

Summary: The Bears and Colts have strong kicking games that will influence any fourth-down decisions made by Smith and Dungy. Neither Chicago kicker Robbie Gould nor Indianapolis’ Adam Vinatieri have missed a field-goal attempt in the playoffs, and both have range to 50.

The Bears’ Brad Maynard played a valuable role punting against the Saints, and the Colts’ Smith has been solid all season.

lonnie.white@latimes.com