Balance is essential for winning a national championship.

Since 2010, only 1 team has won it all without being in the top 30 nationally in both offensive and defensive efficiency, per KenPom.com. That was the 2014 Connecticut Huskies, who were 39th in offensive efficiency and entered the NCAA tournament as a 7-seed.

That UConn team barely made it out of the first round, beating Saint Joseph’s in overtime in the first round before Shabazz Napier and a top-10 defense carried it to the title. The Huskies were an outlier in many ways.

If the next national champion is going to look like the rest from the previous decade, then there are only 2 Big Ten teams that are true contenders. Both are currently on the outer fringes.

One is Wisconsin, which is 34th in offensive efficiency and 37th in defensive efficiency. The other is Illinois, which is 16th in offensive efficiency and 35th in defensive efficiency.

And in Sunday’s 93-85 win at Michigan, the Fighting Illini played as the version of themselves that could make them a danger to any opponents this March.

An offensive clinic

Illinois was a scorching 56.7% from the field Sunday — easily its best showing in a Big Ten game. The Illini have only topped that in wins over St. Francis, Texas-Rio Grande Valley and Missouri. (Which goes to show how terrible Mizzou is this season.)

It’s a credit to how well Michigan has played in recent weeks that the Wolverines stayed within striking distance until Trent Frazier’s backbreaking 3 with 44 seconds remaining. Because when things are cooking like this for the Illini, they are one of the most difficult teams in the country to beat.

The conventional wisdom for beating Illinois is to deny Kofi Cockburn. But Brad Underwood’s first-half game plan took the teeth out of that strategy. Illinois launched 3s early and often.

Alfonso Plummer, who is scorching his way into the final month of his college career, drained 5 of 8 3-point attempts in the first half. Frazier added 2 more. Even 6-10 Coleman Hawkins nailed one.

Cockburn “only” had 8 points at halftime, but the Illini were up by 8.

With Michigan forced to respect the 3 in the second half, the big man took over. Cockburn somehow passed up Plummer, finishing with a game-high 27 points. After launching 17 3-pointers in the first half, Illinois attempted only 3 in the second — one of which was Frazier’s dagger.

Everything was so in sync for the Illini that there was virtually nothing Michigan could do defensively to stop it. Illinois shot 70.8% from the field in the second half.

When a team gets on that kind of heater, you almost always expect to see it happen in its own gym. The fact Illinois put together such a performance on the road bodes very well for March.

But it wasn’t the only thing to be encouraged by from Sunday’s performance.

Is Andre Curbelo finally back?

Illinois is only a Final Four team if Andre Curbelo is playing a significant role. And through no fault of his own, we haven’t known whether that’s going to be the case most of this season.

Throughout the year, Curbelo has dealt with the aftermath of a concussion he suffered in a preseason exhibition game. As was pointed out in the telecasts of both Illinois games this week, he came into the week having only participated in 18 practices since the start of the season.

That’s maybe one-fifth of the way to where he should be at.

As a result, it’s hard to know how much Illinois can get from him and for how long.

But if the Illini can get something like Sunday’s performance every game — or even every other game — they reach another gear.

Curbelo played 20 minutes at Michigan, marking just the fourth time he’s played at least half of a Big Ten game this year. He scored 12 points on 5 of 7 shooting from the field. It’s the only time he’s been in double figures in Big Ten play other than both games against Purdue.

Moreover, Curbelo played with energy. There’s a reason he was the Big Ten’s Sixth Man of the Year last season. It’s not just that he can score off the bench. Curbelo plays a contagious form of basketball. The other 4 Illini on the floor have to up their energy to match his.

Frazier plays the game a similar way. So when Illinois has 2 such players on the floor, it becomes a truly dynamic team.

Curbelo’s continuing recovery from post-concussive symptoms makes for one of the most interesting X-factors in this year’s NCAA tournament. To win a championship, a team must win 2 games in 3 days on 3 different occasions.

That will pose a major test of stamina for a player who does not have the same legs as his teammates. But if Curbelo can pull through, Illinois has a chance to do something special.

The numbers don’t lie.