INDIANAPOLIS — A change at the most influential position didn’t achieve the desired results. The Indianapolis Colts’ offense remains broken. Anthony Richardson? Joe Flacco? Is there a Plan C? Colts coach Shane Steichen’s decision to bench his 22-year-old quarterback in favor of his 39-year-old backup resulted in the worst offensive performance of the season in a 21-13 loss to the Minnesota Vikings Sunday night at U.S. Bank Stadium. Steichen benched Richardson last week because he believed Flacco gave the Colts the best chance to win. He misspoke. Gus Bradley’s defense gave Indy the best chance — honestly, the only real chance — to upset quarterback Sam Darnold and the 5-2 Vikings. “I thought our defense did a helluva job,’’ Steichen said. It generated three takeaways, including defensive lineman Grover Stewart’s sack/strip/fumble of Darnold that defensive back Kenny Moore II returned 38 yards for the Colts’ only touchdown and a 7-0 halftime lead, along with four sacks and eight tackles for loss. The offense? Not so much. “Anytime you have a day like we had tonight, you’re probably surprised a little bit that you weren’t able to get it going,’’ Flacco said. “You know coming in here against a team like this it’s going to be difficult, but I don’t think you ever anticipate anything like that.’’ Like what? Season lows by the offense in: *Points: 6 on Matt Gay’s 42 and 54-yard field goals. *Total yards: 227. The previous low of 269 came in the week 6 win at Tennessee, which was Flacco’s last start. *Rushing yards: 68. *First downs: 13. *Red-zone trips: 0. The Colts ran exactly six plays inside the Vikings’ 30-yard line, and four came in the fourth quarter after safety Nick Cross’ 20-yard interception return of a Darnold pass. A first-and-10 at the 25 turned into a fourth-and-8 at the 23 that Gay cleaned up with a 42-yard field goal. For perspective, Minnesota snapped 16 plays inside the Colts’ 20-yard line. The Flacco-led offense came up with only two chunk plays in the passing game — 22-yard completions to tight end Kylen Granson and wideout AD Mitchell — while Darnold and the Vikings had seven. Indy converted just 3-of-11 times on third down. Steichen insisted Flacco was “fine’’ after he completed 19-of-27 passes for 179 yards, one interception and a 63.7 rating. He had thrown at least two touchdown passes in eight straight games, excluding his one-play appearance at Houston. When Flacco reviews the video, he might cringe with his decision with 5½ minutes remaining in the fourth quarter. The Colts trailed 14-10 and faced a third-and-2 at the Vikings 40-yard line. He forced a pass to wide receiver Michael Pittman Jr., who was double covered, and it fell incomplete. To Flacco’s right, running back Trey Sermon had drifted out of the backfield and would easily have moved the chains. On fourth down, Flacco missed receiver Ashton Dulin. “There might have been a few completions here and there that we could have had,’’ Steichen said. Is Flacco still the Colts’ starting quarterback moving forward? “Right now, yes,’’ Steichen said. Does he believe Flacco still gives the Colts the best chance to win? “Yeah, right now, yes,’’ Steichen said. Might the quarterback switch have played a role in the rough night by the offense? “I don’t think so,’’ Steichen said. “You just go. It’s just like any position, right? “You’ve got to roll and next guy up.’’ That’s the corner the Colts have painted themselves into. They abandoned their long-term plans with Richardson — young, raw and maddeningly erratic — because he essentially forced their hand by completing 44% of his passes and suffering nine turnovers in six starts. They believed Flacco would offer the type of efficiency and productivity to fuel their playoff push over the second half of the season. The push got much more difficult with a 4-5 record and upcoming meetings with the Buffalo Bills (7-2), New York Jets (3-6) and Detroit Lions (7-1). The Bills visit Lucas Oil Stadium Sunday. Simply put, the quarterbacks are making it too difficult to win. The Colts now have played 11 straight one-possession games, but too often aren’t making the necessary plays to tip the scales in the right direction. “Everything that’s on that field, I’m in charge of,’’ Steichen said. “I wasn’t good enough for the guys today. “Everything that’s on that field, my name’s on it.’’ It’s on Steichen to find a way to get a cleaner, more productive game out of Flacco or whichever quarterback is under center. The Colts have passed for fewer than 200 net yards in seven of nine games, including four straight. The offensive output the past four games: 269 yards, 284, 303 and 227 against the Vikings. And it’s on him to design a run game that averages more than 3.6 yards per attempt. Running back Jonathan Taylor was limited to 48 yards on 13 carries. After picking up 22 yards on the Colts’ first drive that ended when Taylor failed to secure a handoff from Flacco, he was limited to 26 yards on 10 attempts. The run game was never going to be the same without Richardson. He’s Indy’s second-leading rusher with 242 yards. Flacco presents zero threat. “Yeah, we have to be efficient running the football with J.T,’’ Steichen said, “but we’ll get that cleaned up. “I have full faith and confidence that they’ll get that cleaned up.’’ There’s a lot to clean up, especially on offense. “That’s a good football team we played,’’ Steichen said. “But at the end of the day, it wasn’t good enough, and I’ve got to be better for the guys.’’ You can follow Mike Chappell on Twitter/X at @mchappell51.