ALLEN PARK, Mich. -- Jim Caldwell wasn't planning on changes in the middle of the day Monday. By the end of it, his entire offensive staff had been shook up.

And if there's a message out of this, it is a clear one. Caldwell, in his second season as head coach of the Detroit Lions, is on notice. The changes Detroit made Monday, firing offensive coordinator Joe Lombardi and both offensive line coaches, were moves that had to be made. But it is the timing of them which is pretty jarring.

Typically, teams make these sorts of moves on an off week, when there is time to implement changes and to have everyone get comfortable in new roles for a week before their first game. If not then, they could come before a home game, so there are at least familiar surroundings. But that these changes came hours before Detroit was boarding planes for London -- and hours after Caldwell said he wasn't making moves -- screams of something potentially larger at play down the road if things don't get better from the team's 1-6 start.

Caldwell should be coaching for his job the rest of this season, that's what these firings Monday say. He has to improve this team, one that was constructed by general manager Martin Mayhew to win now. It was a team built to win with offense as well, as the Lions spent the offseason revamping their run game only to have it be last in the NFL after seven games.

They retooled the offensive line, but quarterback Matthew Stafford is taking more of a beating than a season ago despite taking fewer sacks. And the offense in general, one that the Lions spent an entire offseason saying they felt so comfortable in, has failed at every turn.

One of Caldwell's most commonly used phrases is that he has a lot of patience, but doesn't have a lot of time. Then two weeks ago, in talking about the run game, he shifted his statement to "we don't have a whole lot of time, don't have a whole lot of patience, either." That might have been the first clue the Lions were on the precipice of making some sort of changes if things didn't improve.

Then came Sunday, when Stafford was sacked seven times and hit 13 times. Where the run and pass protection was porous and the offense in general stagnated after a strong first quarter, gaining 4 yards in the second quarter and losing 1 yard in the third. The offensive inefficiency changed the game and was so emblematic of Detroit's offensive issues this season.

Monday, after evaluating things again between his mid-day news conference and 4 p.m., Caldwell's patience and Lombardi's time had clearly run out. When asked why he made moves this week instead of waiting for the team to return from London, when the Lions would have two weeks to prepare with the new coaches in new roles, Caldwell was succinct.

"We don't have a lot of time," Caldwell said. "We're running out of time."

On the season? Absolutely, if the Lions haven't already had time expire on that. On Caldwell's tenure with the Lions? That remains to be seen, but Monday definitely screamed fix what ails your team or else.