But less than a month into the season, in a rematch of last season’s NCAA championship game against Butler, Irving stubbed his big right toe.

Did more than that, actually.

“A serious injury,’’ said Duke coach Mike Krzyzewski, suggesting that Irving might be out for months rather than days or weeks.

January is almost gone, and Irving is watching from the bench — but not in uniform. His return is uncertain. There has been some chatter about March 1, but that is mere conjecture. The mind-set at Duke is that Irving will be a key part of next year’s team.

So where does that leave the Blue Devils as they prepare to face Boston College at Cameron Indoor Stadium tonight?

“We’re OK,’’ said senior guard Nolan Smith, who has filled the void left by Irving, leading the Atlantic Coast Conference not only in scoring but assists and stepping into the conversation as a possible first-team All-American selection and the ACC Player of the Year. “We can win games, but we know we have a long way to go.’’

Well, maybe in the mind of the Dukies. They take great pride in being reigning national champions, pride that befits their 18-1 record and No. 3 ranking. Only a loss at Florida State has sullied that record.

The Blue Devils have done very little wrong, with or without Irving.

“We’re a good team trying to get better,’’ said Coach K, who has used Smith, senior forward Kyle Singler (Duke’s other All-American candidate), plus 6-foot-10-inch junior Miles Plumlee, 6-10 sophomore Mason Plumlee, and 6-11 sophomore Ryan Kelly to forge a more working-class image of Blue Devil basketball.

“I think our big guys are going to keep getting better,’’ said Krzyzewski, “because they are young players and it’s their time to get better.

“They are a priority. They are not playing behind people. It’s their time.

“I think they go to their strengths initially. Mason has recognized that rebounding is a strength and blocking shots, and not many people rebound well and block shots, so that separates when you can do that. The scoring will come.

“Ryan is a really good outside shooter, but you know he’s blocking shots and he’s rebounding. Miles has given us a lot; this past week he gave us great energy coming off the bench.

“So we are pleased with the way our big men are coming along.’’

The loss to Florida State two weeks ago took away the sense of invincibility that was growing at Duke. Coach K said he saw the signs, even though no one was willing to acknowledge them.

“No one wanted to listen,’’ he said. “We’re a good team trying to get better.’’

Make that a very good team. Singler has been a proven commodity since arriving on campus as a freshman. A year ago, he walked off the court in Indianapolis as the Most Outstanding Player of the Final Four.

This year, he has been reliable and at times spectacular. The same can be said for Smith, who has emerged as one of the premier go-to guys in college basketball.

“Nolan is having a great year,’’ said Krzyzewski, “and he had a great year last year and he’s improved even more. He’s got a lot on the plate for us, especially since Kyrie’s injury, handling the ball, defending the ball, scoring the ball, leading the team. He’s done all of those things at the highest level. He’s having an All-American type of year.’’

The Devils get their next test tonight against a BC team that may have overachieved in some people’s minds and is coming off a second-half meltdown against the same Florida State team that beat Duke.

Coach K has nothing but good things to say about first-year coach Steve Donahue, who has guided the Eagles to a 14-6 record.

“He has done a really good job with a veteran BC team,’’ said Krzyzewski. “They have really good talent. But a new coach has to implement a new system and sometimes that’s harder to do with older guys than younger guys. They seem to have responded really well and he obviously did a great job at Cornell.’’

As for his own team, Krzyzewski also likes what he has seen in many areas.

In typical Duke fashion, he spreads the wealth to all levels.

“It’s a collective effort,’’ he said. “As a coach, that’s one of the main things we try to do here because we are a program that has a lot of good things happen and you don’t stay that way without continued hunger and a pursuit of becoming the best you can be.’’

Duke is doing that each game, step by step, and while the term “great’’ may not be applicable yet, the Devils are working steadily on achieving that status once again — with or without Kyrie Irving.

Mark Blaudschun can be reached at blaudschun@globe.com.