Andrew Luck didn't take his big mistake sitting down Monday.

One day after perhaps the most embarrassing moment of his short NFL career, Luck blamed himself for giving away at least nine points in Sunday's debacle at Pittsburgh — two on what some have dubbed the butt safety.

"Take it as a learning situation. What can you do differently? Try to inch forward and take a sack on the half-yard line or spin around, try and get up and get the ball in the vicinity of a receiver to throw it away," he said. "But yeah, bonehead play by me."

Nobody has been more critical of the Colts quarterback than Luck.

During the offseason, he repeatedly brought up the seven interceptions he threw in two playoff games last January.

After a Week 1 loss at Denver, he described a fourth-down play call at the goal line as a stupid decision that "will remain so for perpetuity." And after throwing a late interception in the red zone in Week 2, a miscue that allowed Philadelphia to rally for a win at Lucas Oil Stadium, Luck said he was disappointed in himself.

But Sunday's poorly timed stumble will be tough to live down.

Two plays after linebacker Andy Studebaker recovered a Steelers fumble at the Colts 5-yard line, Luck tripped over the feet of center Jonotthan Harrison, fell to the ground at his own goal line and then tried to throw the ball into the flat from the seat of his pants. With no receiver close to the ball, Luck was called for intentional grounding in the end zone. After pleading with officials to rescind the penalty, and the safety, on the sideline, Luck acknowledged Monday he didn't have a case.

"It was probably the right call," he said.

Teammates and coaches insisted there was a lot more blame to go around.

Indy's surging defense disappeared. The Colts (5-3) couldn't get off the field, allowed a season-high 51 points and didn't even force a punt. It was a complete reversal from the previous four weeks.

What had looked like an improved offensive line allowed two sacks and seven quarterback hits, putting Luck under constant duress.

The ground game that allowed Indy to play keepaway during much of its five-game winning streak finished with only 10 carries.

Following the safety, Pittsburgh gave Luck another kick in the pants by driving for a touchdown that turned a 42-34 game into a 51-34 kick blowout.

"You don't convert on third down, you can't get off the field on third down. You line up on special teams to block a field goal and they get you to jump and you give them a fresh set of downs and then it costs you a touchdown," coach Chuck Pagano said. "It's bad football. It's not intentional, but its bad football and you're not going to win games playing like that."

Now the AFC South-leading Colts must cope with more uncertainty heading into next Monday's matchup against the Giants (3-4).

It appears running back Trent Richardson (hamstring) and veteran receiver Reggie Wayne (left elbow) may return next week after sitting out Sunday. Starting outside linebacker Erik Walden is listed as week to week with a hip flexor injury and the Colts' No. 1 cornerback, Vontae Davis, is listed as day to day after missing most of Sunday's game with a knee injury. Pagano said an MRI on Davis was negative.

The strangest part of Monday may have been the case of safety LaRon Landry. He was eligible to come off the suspended list Monday after serving a four-game suspension for violating the league's substance-abuse policy but apparently was nowhere to be found.

"I have not seen him yet," Pagano said when he spoke to reporters at about 4 p.m.

The good news is that Indy has an extra day to get healthy and figure out corrections. But there's even a downside to that.

"We've got a big game coming up that we're all excited for and probably can't get to fast enough so we can get this taste out of our mouth," Pagano said.

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