By Dave Wischnowsky –

(CBS) The good news for this young Illinois basketball team is that it’s playing in the postseason. The bad news is that the postseason is the NIT. And the frustrating news is that I think it could have instead been the NCAA Tourney, if only a few buttons had been pushed earlier.

And, yes, John Groce, I am looking at your trigger finger.

Overall in Year 2 of the Groce Era in Champaign, I was pleased with the Illini coach’s job. As he works to stabilize and strengthen his roster for the long term, he’s been forced to deal with a lineup that’s long on inexperience and short on shooting. Throughout this season, he didn’t allow the Illini’s spirit or effort to falter, even during an eight-game losing streak. And yet again, he has his team peaking down the stretch when games matter most.

But my beef with Groce for 2014-15 is that he didn’t peek down his own bench earlier this year. Because I do believe that if he had inserted freshmen Kendrick Nunn and Malcolm Hill into the starting lineup in place of fifth-year seniors Jon Ekey and Joseph Bertrand a little earlier, Illinois very possibly would have nabbed the one or two more Big Ten wins it needed to be selected for the Big Dance.

And while I’m surely not the only to hold that theory, I am the one who has crunched the numbers to help back it up.

First off, note that since the Big Ten season began on Dec. 31, Illinois played 20 games against conference opponents (including two in the Big Ten Tournament). During the first 10 of those games, all of which included Ekey and Bertrand in the starting lineup, Illinois went just 2-8 against a group of foes with a combined winning percentage of .615.

During the latter 10 games, however, all of which included Nunn and Hill in the starting five, the Illini went 6-4 against opponents with a .649 winning percentage.

That means that Illinois has played its best basketball during the most difficult stretch of its conference schedule after playing its worst during the easier portion.

On Feb. 9, when Groce finally green-lit the starting lineup change against Penn State and swapped the seniors for the freshmen, the fortunes of the team seemed to immediately change. But what you may be surprised to learn is that it wasn’t so much of an offensive spark that the revamped lineup has given Illinois since then, but rather a defensive one.

Consider these numbers: During the first 10-game window, Nunn and Hill averaged a combined 9.1 points per game in 27.8 minutes off the bench, while Ekey and Bertrand produced 18.3 points in 59.7 minutes as starters.

During the second 10-game window, the freshmen combined for 18.2 points per game in 52.5 minutes as starters, while the seniors totaled 8.9 points in 37.4 minutes as reserves.

If you add up their points-production per game, it’s pretty much a wash. In fact, the four players actually combined to score more (27.4) during the first 10-game stretch than they did during the second (27.1), although the quartet’s points-per-minute production did increase from .301 to .313 after Nunn and Hill joined the starting five.

Just by simply watching games, it very much felt as if the freshmen rejuvenated the offense, but in fact the big difference between the old Illini lineup and new one has instead been on the defensive end.

During the first 10 games, Illinois averaged 62.9 points, which actually dropped down to 57.8 after Nunn and Hill became starters. Defensively, however, Illinois was giving up 69.7 points per game during the first 10-game stretch and then saw that number plummet by nearly 12 points to 57.9 with the reworked lineup.

That’s a huge difference, and the key to Illinois’ resurgence.

Groce has said that he didn’t decide to start Nunn and Hill until “the light came on” for them defensively. And perhaps that is true. But if so, then that light came on remarkably strong once their defensive switch was suddenly flipped.

The other scenario, perhaps more likely, is that Groce was underestimating his athletic youngsters a bit, and hesitant to abandon his experienced senior starters. Such a mindset is understandable, but in a season where just one or two more wins could have meant the difference between the NIT and the NCAA Tournament, that doesn’t necessarily make it excusable.

When Nunn and Hill became starters was when Illinois’ season truly began this year. And while the freshmen’s emergence does bode very well for the future, I can’t help but lament that getting them off the bench might have helped the present more too.

Because while Illinois is waltzing into the NIT on a high note, it still would be nicer going to the Big Dance.

Follow Dave on Twitter @wischlist and read more of his columns here.

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