Bears notebook: Khalil Mack day-to-day with shoulder injury

The Bears’ defense, reeling after a second consecutive meltdown performance, could have more problems this week. Outside linebacker Khalil Mack suffered a shoulder injury against the Lions and is day-to-day.

Mack, who was shut out on the stat sheet against the Lions — after a sack was nullified by a penalty — did not practice Wednesday as the Bears began preparations for the game Sunday against the Texans at Soldier Field.

Coach Matt Nagy said he did not know when Mack suffered the injury. Mack played 55 of the 68 defensive snaps against the Lions (81%, his second-lowest percentage of the season). Mack has played in all 12 games this season, but wear-and-tear could be taking its toll. He previously was on the injury report with ankle, back and knee injuries.

“When you watch that game, he’s getting banged around a lot,” Nagy said. “He’s got guys banging him on every play. So I think it was just a little bit of some different times in the game where he got hit. At this part of the season you want to take care of him. We obviously need him. That’s why he’s day to day right now.”

Injury report

Cornerback Buster Skrine (concussion protocol), linebacker James Vaughters (knee) and wide receiver Darnell Mooney (personal) did not practice. Defensive end Akiem Hicks, linebacker Danny Trevathan and tight end Jimmy Graham were rested.

Robinson’s misstep

Wide receiver Allen Robinson said he did not see Lions cornerback Amani Oruwariye slip on a third-and-five reception with 22 seconds left in the fourth quarter Sunday.

Oruwariye’s slip gave Robinson room to get the first down, but instead Robinson turned and stepped out of bounds a yard short. David Montgomery was stopped for no gain on fourth-and-one, clinching the Bears’ sixth consecutive loss.

“There’s no way I could feel that,” Robinson said. “So I turned toward the sideline, I turned a little wide, I guess, but I already was kind of close to the sideline, and once I turned wide, as I’m kind of pushing up the field, I kind of see the [chain-gang] marker, but the marker was a little bit different than where the marker was on the ground. So as I’m kind of pushing up, and then I look on the ground, I try to step over the marker, but obviously I came up a yard short.

“Looking back at it, if I didn’t turn as wide, I may have been able to get up the field or kind of go forward. But I’m thinking about clock, If I stalemate and it’s third-and-short and the clock keeps running, I can’t stalemate. That was the only thing going through my mind at that time was protecting the catch.”

Falling fast

After allowing 460 yards and 34 points to the Lions, the Bears’ defense dropped to 15th in yards, 17th in rushing yards, 17th in passing yards and 12th in points allowed this season. Four weeks ago, they were ninth, 14th, seventh and seventh in those four categories..