BOSTON — Iowa State will trudge into college basketball's offseason with nightmares of missed layups, bricked open looks and a 72-69 loss to Illinois that separated the Cyclones from just the third Elite Eight appearance in program history.

This is a team and program that in many ways exists without ample room for error, relying not on elite athletes and scorers but a willingness to buckle down on defense, scrap after loose balls and force opponents into a discomforting, cage-fight sort of atmosphere.

"You know, unfortunately, we weren't able to take advantage of opportunities when they presented themselves, and Illinois also did a very good job of not allowing anything to come easy for us," coach T.J. Otzelberger said.

"I thought we showed a lot of competitive spirit, but for us to be successful against a really good team, we've got to do some things in the margins better in terms of scoring off turnovers. We've got to rebound a little better and some things like that that could have put us in a different position."

The loss can serve as a metaphor for the program's current status: Otzelberger has turned Iowa State back into a very good program, just not yet a great one.

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But the growth in his three seasons is obvious. After inheriting a team that went winless in conference play, Otzelberger has led the Cyclones to a pair of regional semifinals and won 29 games this season, the second-most in a season in school history.

The arrow is pointing up. Otzelberger is already the only Iowa State coach to make two appearances in the Sweet 16 and one of three to reach the tournament three years in a row, along with Tim Floyd and Fred Hoiberg.

While devastated by Thursday night’s loss, the core of this year’s roster "elevated our program," said Otzelberger.

"They should be remembered as a group that was extremely hard-working, that made each other better, and a group that the unity that they had allowed them to play at a higher level as a group maybe than the parts because they were so committed to one another."

After thriving in the deep waters of the Big 12, perhaps the best conference in the country, the Cyclones were sent home by an opponent who in one way reflects what the program is missing: a take-charge scorer capable of finishing at the rim and lifting an average offense to a higher level.

Illinois has that in senior All-America wing Terrence Shannon Jr., who battled foul trouble by still managed to score 29 points in 30 minutes. Shannon has scored at least 25 points in all three tournament games. With Shannon on the court, Illinois’ offense may be the best in the country; when he’s a bystander, the Illini look like Iowa State.

"He's a really tough cover," Otzelberger said of Shannon. "He's as aggressive of an offensive player as there is in the country, and he is playing at such a high level. You can't let a guy like that get the opportunities that we allowed for him early where he got his confidence going."

That the Cyclones made just 13 of 27 layup attempts − some with players literally uncovered by the basket − may be the single biggest factor behind the loss. But the most frustrating may be the inability to nail down key stops on crucial possessions in the second half, especially after Shannon returned to the court with over five minutes left and Illinois ahead 55-51.

"We're at our best when we're dictating and pressuring the basketball and when we're chasing down rebounds and we're attacking off turnovers," said Otzelberger. "We weren't able to do those things to the level or the standard that we try to uphold today."