Running the table is in play here.
Michigan State was "rebuilding" last year, inasmuch as a team that has made every NCAA Tournament since 1997 rebuilds.
(They should hang a banner for that. "1996: LAST NATIONAL INVITATIONAL TOURNAMENT APPEARANCE")
With the offense led by Eron Harris and three freshmen, it was understandable that the Spartans would finish a middling 6th in Big Ten offensive efficiency. It also didn't help that Miles Bridges missed some time, or that Tom Izzo was afflicted by a condition that led him to look at Nick Ward and Kenny Goins and conclude that yea, sure, those guys ought to be on the floor for roughly the same amount of time.
It would be a shame if Bridges gets hurt again this year, and it would be outrageous were the latter to come to pass. But assuming these things don't happen—watch out. The Spartans return more freshman-to-sophomore minutes than anyone else in the Big Ten, and the expected sophomore leaps figure to be supersized when talking about the 4 & 5 star pedigrees of those sophomores. Bridges might well have been a lottery pick had he chosen to leave school early, and Ward was actually even better when he wasn't cozying up to Izzo on the bench. Bridges made 54 percent of his 2s and 42 percent of his 3s in Big Ten play, while also rebounding at an elite level on the defensive end. Ward was merely the best offensive rebounder in the league, drew a ton of fouls, and blocked shots at an elite level.
Former top-30 recruit Cassius Winston suffered only from the not-uncommon malady of turnovers that afflicts virtually every freshman point guard, and I expect a rapid decline in that area as a sophomore. If that happens, he's likely the best point guard in the league. So, you have the best point guard, the best scorer, the best interior player, and defense and rebounding is accounted for as well.
And I haven't even gotten to former top-20 recruit, Joshua Langford. Or this year's class, which features top-10 big man Jaren Jackson, and a couple of other top-100 freshmen. And there's also Tum Tum Nairn to think about, Gavin Schilling returning from injury, 23-year old transfer Ben Carter (who averaged 9 & 6 at UNLV two years ago), Matt McQuaid, or the fact that Tom Izzo is the coach.
And, as luck would have it, Michigan State also has an easy league schedule.
OK, so the Spartans are winning the 2018 Big Ten Championship. Congrats. But how good is this team nationally? Well, for that, let's see if the Spartans qualify as a Category 5 Roster. As John Gasaway put it
A category 5 roster is one that returns at least 40 percent of the previous season’s possession-minutes and adds a freshman class with at least 25 recruiting points.
The first one is easy—MSU returns about 75 percent of last year's possessions and minutes. The second piece...no, Michigan State adds just 8 points. Then again, it's actually impossible* to obtain Category 5 status with a 3-man class, and since the Spartans actually only had three scholarships to hand out, that seems like an unfair standard. However, it should be noted that if you add last year's class to this year's class, they blow through 25 points, easily. However, if we treated last year's freshmen as this year's freshmen (for the purpose of this exercise), the returning conference minute total drops to a little over 30 percent. Of course, you could "reclassify" everyone but Langford, for instance, and end up with over 40 percent and still end up with close to 30 recruiting points.
So, this isn't strictly a Category 5 roster. However, it might well be the sophomore version of that (hey, @JohnGasaway, please invent that!).
The last great shot at a national title was Bo Ryan's last full season in 2015. Prior to that, we had the Indiana Zeller team, the Sullinger seasons in Columbus, the Oden season in Columbus, and then we're back to Illinois' 37-win team in 2005. But none of them won the NCAA Tournament, and the Big Ten's 17-year drought continues. That's a long time—one of the captains on the team looks like this now:
The Big Ten is a much better conference than the 17-year drought would indicate. It's time. And Michigan State seems primed to break through.
(*) OK, it's not "impossible" for a 3 scholarship class to obtain 25 recruiting points. For one, a coach might convince a high-profile recruit to walk on. More reastically—and this is still completely unrealistic—there might be a tie for the top player in the country, and the school could get both players alongside another top-10 player.
But yeah, basically impossible.