Illinois has been in a postseason coma since its 2005 march to the national championship game.

That run remains not only the last time the Fighting Illini reached the Final Four, but the last time they even made it as far as the Sweet 16. The Illinois football team has reached the Rose Bowl more recently than that.

Given the comparative historic success of Illinois’ headlining programs, that is difficult to fathom.

But even that ’05 team, which didn’t lose until the final game of the regular season, came precariously close to being just another bunch of underachieving Illini. Playing a virtual home game at Allstate Arena in suburban Rosemont, the Illini spent the better part of the 2005 Chicago Regional Final getting their doors blown off by Arizona.

Instead, it turned into the moment those Illini ensconced their name in legend.

Illinois erased a 15-point deficit in just under 4 minutes, then knocked off the shellshocked Wildcats in overtime. Deron Williams, Luther Head and Dee Brown guaranteed themselves Illinois immortality in the process.

The stakes were not nearly as high at State Farm Center on Thursday night, and the timeframe was nowhere near as tight. But in erasing an 18-point second-half deficit against a different set of Wildcats, Illinois showed a level of guts that hasn’t been seen in many a March.

Restoring the natural order

The week dawned with the natural order of the Illinois-Northwestern rivalry feeling completely upside-down.

Even calling it a rivalry is only true with regards to geography. Illinois could lose the next 98 games in the series before Northwestern pulled even.

But this season, it is the Cats who find themselves contending for the Big Ten title — something they haven’t accomplished since 1933.

Thursday marked the first time Illinois faced a ranked Northwestern team since Jan. 11, 1969. The Wildcats were on a mission to sweep the Illini in a season for the first time since 1966.

And boy, did it look like that’s exactly what was going to happen for at least 30 minutes of game time.

Northwestern, woefully disrespected by bookies as a 7.5-point underdog, rocketed out to a 37-19 halftime lead. Point guard Boo Buie outscored the Illini by himself — 22 points for Buie, 19 for Illinois.

The Illini went broke against Northwestern’s defense, shooting 0-for-11 from 3-point range while the Cats scorched the nets by drilling 8 of 16 from long distance.

The Wildcats looked halfway to chasing down history. Finish out this win, have Indiana upset Purdue on Saturday, and suddenly Northwestern’s first Big Ten title in 90 years was crystalizing.

Illinois, on the other hand, looked like the same old talented but underachieving Illini that have routinely made March the most disappointing month in Champaign-Urbana.

Then, in a flash, the Illini looked more like 1 of the most defining teams in program history.

Terrence Shannon Jr. was like Williams and Brown rolled into a singular dominant package, scoring 24 of his 26 points after the break. He missed just 1 shot from the field in the second half.

Matthew Mayer played the role of Head, adding 14 points and 5 rebounds in the second half after going scoreless with 3 boards in the first.

Despite allowing Buie to go off for 35 points, and leading for just 1:40 of the entire game, Illinois pulled off the 66-62 win.

It’s fitting that Shannon and Mayer are the guys lifting the Illini. These were the transfers hand-selected by Brad Underwood to keep Illinois competitive after losing Kofi Cockburn, Trent Frazier, Alfonso Plummer and Andre Curbelo from last year’s team.

They may also be the guys who can take Illinois to the next level.

With all of their teammates befuddled by Northwestern’s defense, both had an outsized impact on the unlikely comeback. And it is their positive postseason history — Shannon at Texas Tech and Mayer at Baylor — that’s going to have an outsized impact on what this Illinois team does next month.

The start of something bigger?

Maybe this comeback will be the start of something big for Illinois.

And hopefully this game — easily among the 5 best played in the Big Ten this season — portends things to come for Illinois and Northwestern as more than an empty-calorie rivalry.

To most Illinois fans, the definition of a rivalry is the Braggin’ Rights game against Missouri.

There’s also plenty of vitriol for Indiana, though Hoosiers fans focus their energy on Purdue, Kentucky and maybe even Notre Dame before the Illini ever come into the picture. (There’s also a strong anti-Notre Dame sentiment among Chicago-area Illinois alums, but the Illini and Irish rarely cross paths.)

But it would be good for basketball in the state of Illinois, and the Big Ten in general, if games against the Wildcats mattered more often. For it to feel equally important to both sides. Ideally, we aren’t waiting another 54 years for Northwestern to be ranked when it plays Illinois.

It took Chris Collins 6 years to put a group like this together, so it may remain wishful thinking for classics to become a regular occurrence.

But the Big Ten Tournament is in Chicago this year. And a rubber match at the United Center would be a welcome sight in this rare season that Illinois-Northwestern is a rivalry.