Fran McCaffery’s squad is riding its first four-game Big Ten winning streak since the 2016-17 season, so it’s coming back to Carver-Hawkeye with momentum.

After pulling off an 89-82 victory at Penn State and avoiding an upset, the Hawkeyes will turn their attention to Illinois on Jan. 20.

And this time around, Tyler Cook might be suiting up for the Black and Gold. Two of Iowa’s conference road wins have come without Cook on the floor, so the Hawkeyes have shown they can compete without their star.

But having Cook back would do wonders for Iowa’s depth and production inside against an Illinois team that is coming off a 95-68 throttling of Minnesota.

Cook warmed up before Iowa’s win over the Nittany Lions, and McCaffery said he could run on the ankle fine, but the problems showed up when it came to making cuts.

“He had no explosion,” McCaffery said. “To his credit, I think he realized he really wouldn’t have helped us if he’s out there laboring. He’s just going to be diligent as he has been with rehabilitating that thing, so he can get ready for Sunday.”

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As important as he is, Iowa has been solid inside — especially defensively — without Cook.

In the two games Cook missed — road wins over Northwestern and Penn State — the Hawkeyes have shut down some of the top big men in the conference.

In the last three games, Iowa has held Dererk Pardon, Kaleb Wesson, and Lamar Stevens each under 10 points.

That is likely not the same thing the Hawkeyes would have done last year. Last season, teams scored buckets at will, whether in the paint or on the perimeter.

The change in defensive efficiency is a big part of how Iowa has found ways to win in close games and has been a key in surpassing last season’s win total with just under two months left in the season.

“[We’ve been] revisiting defensive principles, stuff that we’ve been working on ever since last season,” said forward Ryan Kriener, who has played a key role in Cook’s absence.

The Illini boast just a 5-12 record (1-5 Big Ten), but their last three losses to No. 21 Indiana, Northwestern, and No. 2 Michigan have all been by 10 points or fewer.

When Illinois is on, it’s on, as it showed in its slaughtering of Minnesota on Wednesday. The Illini shot 56.1 percent from the field against the Gophers and outscored Minnesota in the paint, 52-38.

After a solid freshman season, Trent Frazier has continued to be stellar in Champaign. The guard from Wellington, Florida, enters the game averaging 14.8 points and 2.9 assists.

Minnesota entered the contest with a 13-3 record, including a 3-2 mark in Big Ten play, and got smacked in the mouth. If Iowa doesn’t want to suffer the same fate, it has to be ready.

“The margin for error [in the Big Ten] is very small every night,” McCaffery said. “You can’t relax against anybody at home or on the road. Every team has a great coach, every team has really good players … It’s hard to get somebody down, and bury them, and pull away.”