Four weeks ago Purdue wasn’t so much as a blip on Michigan’s radar.

When fans anxiously went through the schedule searching for every win on the calendar, there was no hesitation or second-guessing when the Sept. 23 bout with the Boilermakers appeared. Circle that one in ink, because Purdue doesn’t have a shot. Nobody would’ve disagreed.

Michigan starts B1G play 1-0. Move on to the bye week and a much more intriguing game with in-state rival Michigan State.

Pump the brakes on that thought, because the Wolverines aren’t going to be able to steamroll through Purdue this weekend. That once-guaranteed victory for Jim Harbaugh and Co. isn’t a lock anymore.

Jeff Brohm brings the Boilermakers into Saturday’s game against No. 8 Michigan with a 2-1 record. They went punch-for-punch with Louisville in Indianapolis Week 1 and followed it up with back-to-back victories over Ohio and Missouri, the first time the program has won consecutive games since 2012. There’s a new confidence, energy and excitement that’s swarmed Purdue football.

The term “upset” has regained its value in West Lafayette this week. No, this isn’t the same team Michigan thought it would be playing to open the B1G season.

Let’s not get too carried away with the hype. Wins over a MAC opponent and a bad SEC team are important victories for Purdue’s program, no question. Michigan still enters Saturday’s game as a 10-point favorite, and for good reason. The Wolverines are the better, more proven team. They’re more skilled at virtually every position on the field. None of that has changed over the last three weeks.

And if Michigan exerts its dominance this weekend inside Ross-Ade Stadium — which is expected to be sold out for the first time since the 2008 season — the No. 8 Wolverines will head back to Ann Arbor with that perfect 4-0 record. That should be the outcome on Saturday.

If that’s what should happen, why is the game now considered a challenge for the Wolverines?

Michigan’s performance this weekend matters. Red zone consistency matters. Converting on third down matters. Turnovers matter.

Those things haven’t mattered against Purdue in quite some time.

This isn’t the same Purdue team from the last decade, it’s one that plays with a lot of swagger and confidence. It plays hard every down and hasn’t given up until the final second is off the clock. That’s the mentality Brohm has brought to West Lafayette.

In the past, mistakes haven’t mattered when playing the Boilermakers because, well, it was Purdue. Opponents didn’t have to play mistake-free football or play at a high level. A win was essentially guaranteed, regardless of performance.

Brohm’s defense has forced eight turnovers and the offense has converted on all 13 trips to the red zone. It isn’t the same team that threw in the towel at the end of the first quarter and was embarrassed by the end of every game.

This is probably a week where water finds its level. Michigan’s red zone troubles — scoring one touchdown on 10 trips — probably won’t last all season long. The Boilermakers haven’t played a team nearly as talented as the Wolverines, especially on the defensive side of the ball. This could still be an old-fashioned whoopin’ if Michigan plays to its potential.

It’s not going to be quite as easy as it was once perceived, though. And, unlike the past, Michigan will actually have to play well to post a convincing win in West Lafayette.

Purdue is playing much better and the Boilermakers will put up a better fight than anything we’ve seen in nearly a decade. But Michigan is still Michigan and it’ll be the more talented team in the stadium on Saturday.

It’s just not a guaranteed victory, anymore.