Bears coach Matt Nagy does nothing to curb speculation about linebacker Roquan Smith

The sudden absence Sunday of Bears linebacker Roquan Smith remained mysterious Monday, and coach Matt Nagy offered no clarity as speculation swirled about why he was inactive and when he’s coming back.

Nagy was unwilling to give a definitive answer to roughly a dozen questions put to him by reporters at Halas Hall, even about whether Smith will be on the team’s flight Thursday to London.

‘‘I’m just gonna say it was a personal issue,’’ Nagy said. ‘‘I’m not getting into anything else. I’m just gonna completely keep it at that.’’

Nagy held to that, returning to the ‘‘personal issue’’ line several times. By giving no parameters about what is happening with Smith, the silence only fuels the guessing game.

Asked directly whether it was a legal situation, Nagy replied, ‘‘Personal issue.’’ He responded the same way to a question about whether it was disciplinary.

The Bears announced less than two hours before their game against the Vikings that Smith was ‘‘doubtful’’ because of a personal reason. He was inactive for the first time in his career.

Nick Kwiatkoski started in his place and led the Bears with nine tackles as the defense shined. The Bears had six sacks and two takeaways and held NFL rushing leader Dalvin Cook to 35 yards on 14 carries.

‘‘The [good] thing is that these coaches, regardless of any situation, they prep all their guys for that,’’ Nagy said. ‘‘So if something does pop up . . . you’re able to handle it. And I appreciate that.

‘‘As you go through a season as a head coach, this is part of the deal. But, again, from me to you, I’m leaving it at that.’’

Nagy described Smith being inactive as ‘‘a decision that we ended up making’’ because that was ‘‘what we wanted to do at the time.’’ Whether that’s an indication that Nagy made the call rather than Smith is up for interpretation.

Smith practiced all last week and wasn’t listed on the injury report. He was on the sideline during the game but left the locker room before reporters entered. He was scheduled to be at a community event Monday at Maine East High School but didn’t attend.

Nagy said he isn’t worried about rampant rumors or about the possibility that public perception will spiral as a result of the Bears being evasive about Smith.

‘‘That’s all part of your guys’ world and what people do,’’ he said. ‘‘Totally normal that everything, with whatever the situation is — today’s social media and all that stuff. People can say different things. People want to be the first to do this or do that. But I’m not concerned, no.’’

Nagy prides himself on being exceptionally honest with the media relative to other NFL coaches, and this was the most uncooperative he had been at a news conference in his time with the Bears.

He declined to say when he became aware of Smith’s situation or what the timeline is for determining when he will play again.

‘‘Again, personal issue,’’ he said.

Nagy also wouldn’t say whether Smith’s return would be up to Smith or to the team. The Bears play the Raiders on Sunday in London, then have a bye week.

Smith, 22, is one of the Bears’ core defensive players and was second on the team in tackles before Sunday. He was the eighth overall pick in the 2018 draft and is in the second season of a four-year, $18.5 million contract that features a team option for 2022.

Patrick Finley contributed to this report.