What was Mike Tomlin thinking?

This is a smart guy. He’s been around the block. He should know if you’re an NFL coach you don’t casually throw around challenges. He, more than anyone, should know such words can come back to bite.

But that’s what Tomlin did yesterday in Arizona at a AFC coaches breakfast, which was part of the NFL owners meetings.

The background is well known: The Steelers -- coming off an 8-8 season, having lost three regulars already in free agency and faced with the kind of lineup holes this franchise rarely has -- are understandably being downgraded by just about everyone.

Tomlin, presumably, had enough

``That's March talk," he told the assembled crowd/media. ``I'll see you at stadiums in the fall.''

And with that the man known for his way with words uttered the second most famous quote of his six-year tenure as Steelers coach. The first famously was said Nov. 29, 2009 after a loss to the Baltimore Ravens, the third straight for the defending Super Bowl champions, which dropped their record to 6-5.

``We will unleash hell here in December because we have to,’’ Tomlin said -- words he would soon regret..

The Steelers lost their next two games -- to Oakland and Cleveland, no less -- and hell was unleashed on Tomlin ever since for those words.

The Steelers won their final three that season, sort of a belated unleashing of hell, but it was too late and the team did not make the playoffs.

Critics of Tomlin have never allowed those words to be forgotten. No accomplishment -- not another trip to the Super Bowl, not three consecutive 12-4 seasons -- would put those words to rest.

Now, maybe, he has with another gaffe.

In a lot of places, Tomlin would be a hero. He’s had the greatest opening six-year run in Steelers history. But too many won’t give him credit, insisting he did it with Bill Cowher’s players or that his game-day coaching has hurt the team more than it has helped.

At the conclusion of last season, Tomlin correctly called himself an 8-8 coach. He’s also a 63-33 coach with two Super Bowl and four playoff appearances in six years.

He just needs to be a little more careful in issuing public challenges.