View Photo Gallery: The NCAA men’s basketball tournament is underway as teams from across the country vie for the national championship.

The day college basketball junkies circle on the calendar has finally arrived. Sure, the 2012 NCAA tournament officially started Tuesday night with those play-in games the NCAA now considers the first round, but there really is no replacing what will take place Thursday when the round of 64 gets underway.

Sixteen games will span more than 12 hours — and then it all starts again Friday when the other half of the bracket tips off. Keep checking The Early Lead for updates throughout the day and follow along with The Post’s interactive bracket.

First things first, though. Here’s a rundown of the most interesting games to watch Thursday, a couple of potential upsets and two under-the-radar mid-major players who could be household names by the end of the day.

Must-see games

East Region: No. 8 Kansas State vs. No. 9 Southern Mississippi, 12:40, Tru TV

Rodney McGruder (Keith Srakocic / AP)

West Region: No. 3 Marquette vs. No. 14 BYU, 2:45, CBS

Less than 48 hours after pulling off the biggest comeback in NCAA history to defeat Iona in Tuesday’s play-in game, BYU returns to the court for a matchup with Marquette and its two stars, Big East player of the year Jae Crowder and first team all-Big East guard Darius Johnson-Odom. Both Crowder and BYU leading scorer Noah Hartsock (23 points vs. Iona), who may guard each other, have taken long roads to get to this point. Crowder spent time at two junior colleges before coming to Marquette last year, while the 24-year-old Hartsock went on a Mormon mission before starting his four-year career at BYU.

East Region: No. 5 Vanderbilt vs. No. 12 Harvard, 4:40, TNT

Many snickered when the NCAA selection committee claimed it didn’t deliberately match up the two teams whose players likely have the highest combined SAT scores. Both the Commodoes and Crimson have proven they can compete with anyone this season. Led by sharpshooters John Jenkins and Jeffrey Taylor, Vanderbilt is coming off a stirring run to the SEC tournament title that included a win over Kentucky in the finals. Harvard is making its first appearance in the NCAA tournament since 1946, a return to relevance due in large part to Coach Tommy Amaker, a former All Met from W.T. Woodson High in Fairfax.

South Region: No. 5 Wichita State vs. No. 12 VCU, 7:15, CBS

Both Wichita State and VCU have the personnel to advance far into this year’s tournament, but one of these potential bracket busters will be gone before the day ends. Perhaps more intriguing, though, are the two coaches involved. VCU’s Shaka Smart and Wichita State’s Gregg Marshall are considered leading candidates to replace recently fired coaches at Illinois and South Carolina, respectively, and each could earn a serious raise with a run in this year’s tournament. Coming off last year’s surprising Final Four run, VCU has won 17 of its past 18 games and the only loss came on a buzzer beater against George Mason. Wichita State took home last year’s postseason National Invitation Tournament title, and has a legitimate 7-footer in center Garrett Stutz.

South Region: No. 8 Connecticut vs. No. 9 Iowa State, 9:20, TNT

The defending national champion Huskies face an intriguing matchup with the Cyclones, who are making their first NCAA tournament appearance since 2005 under former NBA player, Coach Fred Hoiberg. Iowa State knocked off Kansas, Baylor and Kansas State during the regular season, but Connecticut has enough talent to make another run to the Final Four. Guard Shabazz Napier, forward Jeremy Lamb and freshman Andre Drummond could all be headed to the NBA in a few months, so there’s a chance this may be Coach Jim Calhoun’s last hurrah.

Upset Alerts

West Region: No. 5 New Mexico vs. No. 12 Long Beach State, 4:10, TBS

Long Beach State’s senior-laden lineup and a matchup with a fellow mid-major that favors the same up tempo, aggressive style have made the 49ers a trendy upset pick this year. It doesn’t hurt that Big West player of the year and Cousy Award finalist Casper Ware is coming off a 33-point performance in the conference championship game last week. With Coach Dan Munson, who put Gonzaga on the map with a run to the Elite 8 in 1999, and previous road games at Kansas, North Carolina, Louisville and Pittsburgh, the 49ers shouldn’t be intimidated by the tournament environment. The one problem facing Long Beach State is that starting guard Larry Anderson’s status is still up in the air after missing the Big West tournament with a knee injury.

East Region: No. 7 Gonzaga vs. No. 10 West Virginia, 7:20, TNT

Speaking of Gonzaga, the Bulldogs look ripe for the taking after the selection committee forced them to travel 2,200 miles cross-country and play West Virginia in nearby Pittsburgh. Gonzaga is making its 14th-straight appearance in the NCAA tournament, but Coach Mark Few’s team has made it out of the first weekend just once since 2007. This contest should be a physical affair, which is exactly the sort of style in which West Virginia’s Kevin Jones and Deniz Kilici thrive.

Players to watch

Guard Isaiah Canaan, Murray State, Jr.

Dick Vitale and Isaiah Canaan. (John Wright / AP)

Guard Nate Wolters, South Dakota State, Jr.

The 6-foot-4 Wolters is one of the more unheralded point guards in the country after leading the Jackrabbits to the NCAA tournament for the first time ever. He averaged 21.3 points and six assists per game this year, including a 34-point performance when South Dakota State beat Pac-12 regular season champion Washington by 19 back in December. His height and passing ability could pose problems when the 14th seed-ed Jackrabbits take on No. 3 seed Baylor.

For more updates follow Mark Giannotto, Matt Brooks, Cindy Boren and Post Sports on Twitter.

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