Duncan Keith lost his composure. Now the Blackhawks have lost Keith. It’s only a question of how long.

Keith was offered an in-person hearing with the NHL’s Department of Player Safety on Wednesday for a reckless and dangerous stick-swinging incident during Tuesday’s game in Minnesota. That means he can be suspended six games or more, which means he could possibly miss postseason games. The Hawks have five regular-season games left.

Keith can waive the in-person hearing and do it over the phone to speed up the process. If he goes to New York, the hearing might not be until early next week. If the suspension is six games or more, Keith will have the right to appeal.

Midway through the first period, Keith was knocked on his back and took a one-handed swipe of his stick across Charlie Coyle’s face — drawing blood — as he rolled over to get back up. Keith was assessed a match penalty for “intent to injure” and was ejected from the game.

Keith’s history couldn’t have helped his cause. In 2012, he was suspended five games for elbowing Vancouver’s Daniel Sedin. And in the 2013 Western Conference final, he was suspended one game for a retaliatory high stick on Los Angeles’ Jeff Carter — similar to the one on Coyle — after Carter appeared to slash Keith’s hand.

Technically speaking, Keith is not considered a repeat offender because his most recent suspension was more than 18 months ago, but that only affects the amount of salary forfeited, not the length of a suspension.

Keith’s ejection left the Hawks — already without Brent Seabrook, who was a late scratch with an illness — woefully shorthanded on the back end in a 4-1 loss to the Wild. Jonathan Toews said the Hawks will have to manage without Keith.

“We’ve done it before,” Toews said. “Obviously, [we know] what Duncs means to us. Whatever happens, we’ll make the best of any situation. That’s the only way we can look at it.”