Through two weeks of training camp, their practices were physical, crisp, competitive. In other words, those practices were everything their preseason opener was not.

Coach Mike Tomlin had said he was looking forward to seeing these 90 players take what they had been accomplishing during all of those training camp practices and transfer that into a game setting inside a stadium, but he couldn't have been pleased with the view from the sideline during three excruciating hours of Lions vs. Steelers on Friday night at Heinz Field. It is the rare NFL preseason opener that features compelling individual performances that lead to efficient execution by the group at large, and so let it be said the Steelers were quite common in that regard.

There was enough statistical and anecdotal evidence to explain Lions 30, Steelers 17, and it figures Tomlin will use much of that as a sledgehammer during the final few days of training camp after the team reconvenes at Saint Vincent College. But trying to explain why it unfolded as it did, and what it means for this team that it unfolded as it did, is as difficult as it was to watch it happen in real time.

The Steelers first offensive possession failed because a converted third down was nullified by a penalty, and then on the re-do an open receiver dropped a pass. The second possession ended before it had a chance to get started because of a 9-yard sack on first down. And so it went for an offense that ended the first quarter with no first downs and 1 net yard. One. Net. Yard.

Granted, the offense was hamstrung by the excused absences of Ben Roethlisberger, Antonio Brown, Le'Veon Bell, Le'Veon Bell, and Maurkice Pouncey, and it was prudent to excuse them, but such complete ineptitude was startling. Behind the offensive line that started the Divisional Playoff Game in Denver, the Steelers couldn't or didn't run the football. When they attempted to throw it, penalties, drops, and sacks sabotaged the continuity. Again, 1 net yard in three first quarter possessions.

Conversely, the Lions offense, while similarly devoid of star power except for a cameo by starting quarterback Matthew Stafford, wasn't deterred by the same problems plaguing the Steelers. Or maybe it simply was a function of the poor tackling by Pittsburgh's defense.

For a team that devotes at least one period of every practice to live tackling, the Steelers defense made too many fundamental mistakes when tasked with putting Detroit ballcarriers on the ground. Sometimes the angles were poor. Sometimes the fundamentals at impact were shoddy. The Lions were 8-for-12 in third down situations in the first half, and from the Steelers perspective too many happened on plays where the run-after-catch yards ended up being the difference.

Were it not for William Gay's abuse of a rookie left tackle on a sack-strip that Arthur Moats recovered, and for Dan Orlovsky pulling a Mike Tomczak by flinging the ball into the flat after ducking out of a sack that turned into a pick-six by Doran Grant, the Steelers never would have had the 14-13 lead at halftime that was nothing close to an accurate portrayal of the play on the field.

After the loss, Tomlin used the phrase "big-time negligence" to describe what he had seen from each of the Steelers three units, and that was a fair description. Sammie Coates fumbled twice, for example. Alejandro Villanueva was flagged for a 10-yard penalty and allowed a sack on back-to-back possessions. These are two guys who will be counted upon heavily once the regular season begins, and both ended Friday night being examples of an offense unable "to make the routine plays routinely," which was the way Tomlin put it.

"Negligence" in making "the routine plays routinely" also can apply to the performance of the defense and special teams. The tackling and its contribution to the percentage of failure in getting off the field on third down; the 96-yard kickoff return for a touchdown following the field goal that had restored their lead to 17-16. Examples of "negligence" in making "the routine plays routinely."

The thing about an NFL preseason is that what seems to be true today doesn't necessarily mean anything for tomorrow. And because nothing counts in the standings yet, neither the good nor the bad really means anything because every team is going to start all over in less than a month.

What had been on apparent display so consistently at Saint Vincent College was a no-show on Thursday night at Heinz Field, and that "exhibition" at Heinz Field doesn't necessarily forecast the kind of season it's going to end up being for these Steelers.

It was unpleasant to watch though.