A basketball game is 40 minutes long. That’s obvious.

In each of the last two games, though, Illinois has come out firing on all cylinders in the opening 20 minutes before emerging from the tunnel at halftime freezing cold. They were somehow able to grind out a win over Northwestern on Sunday, but those second-half struggles came back to haunt them in West Lafayette in a 16-point loss to Purdue on Tuesday night.

The Illini were lucky on Sunday. Leading by as many as 18 with 13 minutes remaining in the second half, Illinois saw its lead quickly melt away, with Northwestern using a 13-0 run over a five-minute stretch to put the Wildcats behind by just a single point with six minutes to play.

Behind some solid late free-throw shooting, the Illini were able to escape with a 73-66 win on their home court, but they weren’t as fortunate earlier in the week.

At Mackey Arena on Tuesday, Illinois was rolling in the first half despite playing in one of the most hostile road environments in the nation. Up 21-12 midway through the opening frame, a 14-0 Boilermaker run erased that lead, though the visiting Illini managed to take a 39-36 lead into the break.

After shooting 46.7% in the first half, Illinois went 35.7% from the field after halftime. Illini starters not named Kofi Cockburn combined for just four points and went 2-12, including 0-8 from behind the 3-point line.

Head coach Brad Underwood was blatantly honest about his starters’ off night after the game.

“When Jake and Trent and Da’Monte have a night like they did where we didn’t make shots, you’re not gonna win,” Underwood said.

Though all the starters went cold in the second half, graduate student guard Alfonso Plummer’s drop-off was probably the most alarming. The 3-point specialist went 4-6 from deep and scored 14 points before the break, but he was silent after halftime, missing all three shots he took.

“I feel like they did a really good job with me with no catches,” Plummer said after the Purdue game. “I feel like the only shots I took in the second half were forced, like over my defender, so it’s kinda hard to make shots like that.”

Purdue is undeniably one of the best teams in the country and fully deserving of their No. 5 ranking in the most recent AP poll. With one of the best and most efficient offenses in the entire country, the Boilermakers boast three potential All-Big Ten and All-American players in sophomore guard Jaden Ivey, sophomore center Zach Edey and senior forward Trevion Williams, not to mention veteran playmakers in senior guards Sasha Stefanovic and Eric Hunter Jr.

Losing to this Purdue team is not a step back. In the first meeting between the sides, the Illini forced the Boilermakers to double overtime despite Cockburn playing limited minutes and fouling out in the first OT period and sophomore guard Andre Curbelo unexpectedly returning. 

The way the offense collapsed late on Tuesday was more of a shock than the way the defense struggled to contain Ivey and the high-powered Purdue offense. Though Plummer said he and his teammates “gotta get better on defense” after the loss, the Boilermakers rank sixth nationally in points per game and third in field-goal percentage. Defensive struggles are going to happen in games like that, especially on the road in front of a rowdy, loud crowd.

The lack of second-half offense against the Wildcats was much more shocking. 

The Illini looked like they were going to run away with it on Sunday. Fans could maybe turn off the game and prepare for football parties later in the evening.

Northwestern kept things interesting, though, mostly due to a stunningly poor second-half offensive display from the Illinois starters for the second straight game.

Aside from 10 points from Cockburn, the Illini starters went 1-15 from the field, including 1-12 from deep, and scored seven points.

Northwestern head coach Chris Collins was pleased with his team’s improved second-half defense on Plummer, who scored 16 points on 4-5 shooting from behind the 3-point line in the opening half.

“Just tried to be up in his face a little bit earlier,” Collins said. “I thought Illinois did a good job in the first half. I thought their penetration was getting him open, and he doesn’t need much space.

“I thought in the second half we did a better job and just got into his air space a little bit. And he missed a couple. I mean a couple of the ones he made he probably got a similar look. I mean he just cooled off a little bit, which a guy like that, you gotta hope that’s the case a little bit, too.”

This Illinois team is fully capable of making a deep run in March or at least making it to the second weekend of the NCAA tournament for the first time in 2005. Seeing the way things ended last season makes two-game stretches like this concerning despite the Illini sitting alone atop the Big Ten standings with an 11-3 conference record.

When Plummer is making shots, this team is a contender. When fifth-year senior guard Trent Frazier is playing lockdown defense and coming up clutch in crunch time, this team is a contender. When Cockburn dominates in the paint, this team is a contender.

But when even one of those pieces are missing, upset losses in tournament play grow more and more likely. This week may have just been a fluke, but with postseason play just a few weeks away, the cause of concern is valid and justified.

@JacksonJanes3

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