KANSAS CITY — Nobody ever accused Kansas City Chiefs coach Andy Reid of being an old-fashioned riverboat gambler, but perhaps it was his proximity to the three rivers that flow outside Heinz Field that him in such a mood Sunday in Pittsburgh.

Here was the situation:

–27 seconds to play in the first half.

–Chiefs were deep into the red zone, desperate for some points at the end of the second quarter. It was fourth-and-inches at the Steelers’ 12-yard line.

–Normally that’s time for a 30-yard Cairo Santos field goal, something the Chiefs already accomplished twice in the first half. Santos’ foot produced their only points as they trailed 10-6.

–Points would continue to be at a premium as both defenses were playing well. It figured Reid would go for the field goal, a 10-9 score and the Chiefs got the ball first in the second half.

Reid eschewed the field goal and went for the touchdown.

“We wanted to take advantage of the red zone,” Reid said. “We had a pretty good idea on what they were doing at that point. We’d been down there and saw how they were operating, so I figured we could get inches.”

What the Steelers were doing when playing defense inside their 20-yard line was dropping eight men into coverage and rushing only three on the line of scrimmage. Reid was determined to use the lack of bodies up front.

“It wasn’t even a yard,” Reid said. “It was about the length of the ball, if that. I thought we had a nice, sure yards play right there. We were feeling pretty good about it.”

Jamaal Charles took the handoff and banged into the middle of the line. The Steelers banged back, first by linebacker Lawrence Timmons, who stopped Charles’ progress and then safety Will Allen came up and finished off the play, keeping Charles from falling forward for the first down.

“A touchdown; that’s what we were trying to do,” Reid said. “Hindsight, you say we probably should have kicked it but I knew a couple things there and I felt like we had a lot on the game sheet.”

Did his offense’s first-half performance tempt him to go for the first down because they were having trouble finding the end zone?

“No,” Reid said. “You want as many points as you can get. You want to stay aggressive. When you got that type of distance there, you go get it. There’s a certain mindset here that we’ve been working with the whole season, training camp included.

“When you are put in that situation, you strap it on and go get the thing.”

In this case the thing got the Chiefs, who lost 20-12.

Charles may have summarized it best.

“The Steelers defense wanted it more than us,” Charles said. “Someone came free and we just did not execute on that. There’s a lot of stuff that we did not do today to get that win.”

Now the Chiefs must beat San Diego at Arrowhead Stadium this coming Sunday and hope for help from Cleveland (with a victory over Baltimore) and Jacksonville (handing Houston a loss.) Anything short of that combination and the Chiefs will be at home in January.

“It certainly changes things from how it was,” said quarterback Alex Smith of the Chiefs’ predicament. “But we have a lot of character inside our locker room and I don’t think it will impact our preparation on how we got about this week.”

When the Chiefs are winning and the offense is posting touchdowns and yards, Charles gets a lot of credit. On this Sunday, Charles made sure he got the blame for the 20-12 loss to Pittsburgh. One of the key plays, other than Reid’s gamble, was a fumble Charles lost in the third quarter. Pittsburgh turned that takeaway into a touchdown that made a K.C. comeback hard to fathom.

“I’m sorry for losing the game for us today,” Charles said after the game. “At the end of the day, I know I should not fumble the ball. I made a mistake. I cost my team a turnover today. It kind of hurt because they scored on the drive. It put us in a hard situation.

“I had the ball in the wrong arm. I should have had it in the right arm. That hurt me and it hurt the team.”

NOTES: WR Dwayne Bowe came out of the game with a sprained shoulder and coach Andy Reid said Monday the shoulder was “tender” 24 hours after the game,” but he thinks Bowe will be ready to play Sunday against San Diego. … RG Zach Fulton suffered a sprained foot and was still limping Monday. … OLB Justin Houston picked up sack No. 18 on the season, tops in the NFL.

REPORT CARD VS. STEELERS

–PASSING OFFENSE: C – Quarterback Alex Smith threw for 300-plus yards for the first time this season, completing 68.9 percent of his throws and averaging nearly seven yards per attempt. He did not throw an interception. For Smith’s part, he deserves an A. The Chiefs get only a C because they allowed six sacks and they could not get a pass into the end zone. It’s another week without a wide receiver touchdown.

–RUSHING OFFENSE: F – It’s ridiculous that the Chiefs allowed the run game to become such a minimal part of their offense in this game. Sure, the Steelers crowded the line of scrimmage and they were geared up to put the clamps on Jamaal Charles. What’s new about that? The Chiefs ran the ball 14 times, but two of those were Smith runs away from pass-rush pressure. They only tried to run the ball 12 times out of 66 offensive plays.

–PASS DEFENSE: C – The Chiefs pass defense did a good job of keeping the Steelers offense from exploding for points and yards. They gave up one touchdown pass and one long play. Where they hurt their grade was in the pass rush. Ben Roethlisberger went down just once. There were other occasions where it seemed like he had pass rushers draped all over him, but the Chiefs were unable to chop him down.

–RUSH DEFENSE: B – Pittsburgh’s Le’Veon Bell came into the game with nearly 1,300 rushing yards on the season. But he was cooled off by the Chiefs’ run defense as he carried 20 times for only 63 yards, a mere 3.2 yards per carry with a long run of just seven yards. The K.C. defense stood its ground for the 20 runs by Bell and two end-around runs by wide receiver Martavis Bryant. Eliminating the kneel downs by Roethlisberger, the Steelers ran 22 times for 72 yards.

–SPECIAL TEAMS: C – The kicking game provided next to nothing. The Chiefs ran a fake field goal that worked well and produced a first down. Cairo Santos hit all four of his field-goal attempts.

–COACHING: D – Defensive coordinator Bob Sutton deserves a better grade because his plan against the Steelers highly productive offense held them to their lowest yardage output of the season (282 yards) and it was 143 yards less than their season average. Give him a B. But head coach Andy Reid on the offensive side could not solve the riddle of the Steelers’ defense in the red zone, as the Chiefs visited four times and came away with nothing but field goals. Reid abandoned the running game way too early, making his offense one-dimensional.