The Big Ten’s expanded schedule is shaping up to be quite a grind.

After starting the season with only three teams in the AP Top 25, the league now has six . That’s significant at a time when the Big Ten has increased the number of conference games. Each of the league’s men’s basketball teams will play 20 conference games now — up from 18 a season ago.

Right now, there’s a bit of a lull in the schedule, but league play resumes in early January.

“It’s the toughest year to go to 20 games,” Michigan State coach Tom Izzo said. “I think it’s great. It’s going to be hard on all of us.”

Izzo’s team won the Big Ten last season, but rival Michigan took the conference tournament for a second straight year — and then went all the way to the national title game before losing to Villanova. No. 2 Michigan and No. 8 Michigan State look like the class of the league so far this season, but there’s plenty of competition.

No. 13 Ohio State, No. 15 Wisconsin, No. 23 Indiana, No. 24 Iowa and unranked Nebraska have all had their moments.

It will be a while before Michigan and Michigan State face each other. They play twice toward the end of the season, on Feb. 24 and March 9. By then, the buildup could be immense. The Wolverines are still undefeated after routing Villanova on the road and North Carolina at home. The Spartans have losses to Kansas and Louisville, but their resume includes a 22-point win over Iowa, a 20-point win over UCLA and a 10-point victory over Texas.

Michigan and Michigan State lost key players to the NBA in Moe Wagner, Miles Bridges and Jaren Jackson, but they’ve looked formidable anyway. Freshman Iggy Brazdeikis has fit in right away for the Wolverines, who remain a stellar team defensively.

“End of the season will tell us whether this is our best defensive team ever. Some of the numbers would say that,” Michigan coach John Beilein said. “The whole idea is keeping them out of transition, and then getting us into transition is huge for us.”

Michigan State, meanwhile, is averaging a league-best 87.6 points per game behind the experienced trio of Cassius Winston, Nick Ward and Joshua Langford.

The league schedule actually began back in November, and each team already has two Big Ten games under its belt. It won’t be long before it all starts up again.

“We’ve just got to, I think, get fresh legs back, getting the last nonconference game out of the way, and say, ‘OK, this is now the real stuff,’” Beilein said.

Here are a few more things to watch in the Big Ten:

PARTY CRASHERS: The Wolverines and Spartans look like the most obvious title contenders, but there are five teams tied for first at 2-0 in the league — Michigan, Michigan State, Ohio State, Wisconsin and Indiana. Wisconsin star Ethan Happ is averaging 19 points and 11 rebounds a game.

And keep an eye on Nebraska, which actually leads the Big Ten with an average scoring margin of 20.8 through its 12 games. The Cornhuskers beat Creighton by 19 and Oklahoma State by 23.

The problem for Nebraska is that it already has a conference loss — on the road against Minnesota in the type of game a title contender should probably win.

MORE BIDS?: The benefit of playing a 20-game conference schedule is that teams may have more chances for quality wins. The Big Ten put just four teams in the NCAA Tournament last season but appears on track for more this time around.

DARKHORSE: Purdue won the conference in 2017 and finished one game back last season, but it’s hard to tell what to make of this season’s Boilermakers. They’ve already lost to Virginia Tech, Florida State, Michigan, Texas and Notre Dame, allowing at least 72 points in each of those games.

Guard Carsen Edwards is a Big Ten player of the year candidate. He’s averaging 26 points a game and shooting 40 percent from 3-point range.

DEPTH: Izzo surveys the league and sees plenty of strength among teams expected to be near the bottom.

“I think Illinois’ going to be a tough out, I think a lot of those teams are going to be tough outs. Those are supposedly the worst teams in the league. You want to go to Illinois and play them the way they pressure? You want to go to Northwestern and play?” Izzo said. “You want to go, I’m trying to think who else on the bottom — Penn State? You know, they all can beat you.”

Northwestern lost by two points each to Indianaand Michigan and took Oklahoma to overtime .

MOVING BACK: The last two Big Ten Tournaments were played in Washington and New York, after the league expanded to add Maryland and Rutgers. The event is back in the Midwest now, in Chicago.

By the time the conference tourney starts, these teams should be plenty familiar with each other.