Mark Cannizzaro

Mark Cannizzaro

NFL

Are the Detroit Lions for real?

Are the Detroit Lions to be trusted?

The Lions are 6-3 and leading the NFC North by a game over the 5-4 Packers and Bears, and their first division title in 20 years is there for the taking. They already have swept the season series with the Bears, but have lost once to the Packers, who they play once more.

All the Lions need to do for the next seven games, beginning with Sunday’s game at struggling 3-6 Pittsburgh, is take care of their own business. That, however, is something they have had problems doing for the better part of the past two decades.

The Lions have made the playoffs just once since 1999 — a loss in the wild-card round in 2011 after a 10-6 regular season. Since ’99, the Lions’ record is an ugly 62-146. They have not won a playoff game since the 1991 season.

So, based on its horrible history, there is much to mistrust about this organization — regardless of how talented this year’s team is with a franchise quarterback (Matthew Stafford), one of the best receivers in the game (Calvin Johnson), an explosive playmaker at running back (Reggie Bush) and a stout defensive front (led by Ndamukong Suh).

Brian Billick, a FOX Sports analyst and former Ravens coach, is calling Sunday’s Lions-Steelers game (his third Lions game this season). He told The Post he believes the Lions are the team to beat in the NFC North.

“I think they are for real,’’ Billick said. “The balance they have — particularly offensively — is better than they’ve had the last couple years. Reggie Bush [623 rushing yards] staying in the lineup has been a real positive for them.

“This is the opportunity for them to do something that maybe the former Detroit teams have not done, to solidify who they are,’’ Billick said of Sunday’s game in Pittsburgh and next week at home against the woeful Buccaneers. “They have every opportunity to separate themselves from the rest of the field in the NFC North. They need these next two winnable games to solidify who they are — particularly with Green Bay having to go on the road [at the Giants on Sunday] and Chicago has the Ravens — both without their starting quarterbacks.’’

Fellow FOX Sports analyst Troy Aikman also is a believer in the Lions.

“I do think they’ve grown this year and they’ve won some of the games that were going to be real tests for them,’’ Aikman said this week on the radio. “Maybe this is a year where they’re able to pull it all together. I like Detroit. I like the quarterback. I like a lot of the pieces they have. Now the key is pulling them all together and can they play as a team? This year they seem to be doing that better than they have in previous seasons.’’

Lions general manager Martin Mayhew, who inherited the worst team in NFL history (0-16 in 2008), has to be a candidate for NFL Executive of the Year for the way he quietly has fortified the team. On the active roster, injured reserve and practice squad, there are 25 players Mayhew drafted and 10 who were undrafted rookie free agents or signed off other teams’ practice squads. There, too, are 17 free agents Mayhew has acquired.

The free agents he brought in before this season include Bush, who has been a star, and safety Glover Quin, who has two interceptions. His drafts have been solid, too, with 2013 fourth-round pick DeAndre Levy leading the NFL with five INTs and defensive end Willie Young, a seventh-rounder in April, having started eight games, with two sacks.

Despite their division lead and some of the national attention, the Lions still are battling a respect problem. For example, despite the fact his team had just been beaten by Detroit one day earlier, Bears receiver Brandon Marshall called the Lions his team’s “little brother” while speaking on a Chicago radio show.

Lions left guard Rob Sims responded to Marshall’s chirps, saying, “If you want to go after somebody, we’re standing right here. We ain’t running from nobody.’’

Lions center Dominic Raiola added: “Us as a football team is a reflection of how we are as a city, and we’ve got the city’s back.”

Winning a division title for the first time since 1993 and winning at least one playoff game for the first time since 1991 is the best way for the Lions to have their city’s back, shut Marshall up and show they can be trusted as one of the league’s elite.