Mike Greenberg, Mike Golic and Cris Carter discuss Colts QB Andrew Luck's propensity to congratulate defenders for hard hits. (3:22)

Nothing confuses an opposing NFL defense quite like ... a compliment?

Indianapolis Colts quarterback Andrew Luck has started to confound pass rushers not by his impressive play, but by congratulating defenders for hard hits.

Andrew Luck's routine on-field praise of opposing players has left Colts foes confused. AP Images/Nick Wass

Luck has become known to dole out "nice play, buddy" and "good hit" kudos almost as often as he finds wide receivers open down the field.

"In all the years I've played football I have never heard anything like it," Washington Redskins linebacker Ryan Kerrigan told the Wall Street Journal. "Nothing even close."

Several players told the newspaper that, whether intentional or not, Luck's good-guy act has gotten in their heads.

"I'm like 'what's going on? Aren't you supposed to be mad?' " Philadelphia Eagles defensive back Nolan Carroll told the newspaper. "So then I'm the one who gets ticked off because an upbeat attitude isn't something you see."

Those who know Luck say his unfailing affability isn't an act.

"His idea of trash talk is complimenting people," said Redskins linebacker Trent Murphy, who was also Luck's college teammate at Stanford.

Luck's acts of kindness clearly haven't hurt the AFC South champion Colts (10-4), proving that nice guys sometimes don't finish last.