BLOOMINGTON, Ind. -- Indiana's Cody Zeller turned down one chance to play in the NBA. He couldn't say no twice.

The 7-foot sophomore center who returned to school last fall for one more shot at a national championship announced Wednesday he is leaving college early to enter the NBA draft. The reason was simple.

"The leaders that I came in looking up to and copying their work ethic were Vic, Christian (Watford), Jordan (Hulls), Derek (Elston), a lot of those older guys that are leaving now," Zeller said explaining the difference between last year's decision and this year's. "IU will have a great year next year, but the guys I was closest to are graduating."

The decision was first announced on the website of his family's business shortly before the news conference at Assembly Hall. Zeller said he was eager to start working with the Christian basketball camps being run by his parents and two older brothers, something the youngest Zeller said NCAA rules barred him from participating even though the organization is considered a nonprofit.

Zeller's announcement came 24 hours after 6-foot-5 junior Victor Oladipo announced he was turning pro, too, in the exact same spot -- at midcourt inside Assembly Hall with the school's five national championship banners clearly visible in the background.

These Hoosiers wanted to add a sixth banner but that quest fell short when East Regional champion Syracuse beat the Hoosiers in the regional semifinals. Yet when Zeller walked off the court in Washington that night, he was already pretty sure he had played his last college game.

"After a while, you just kind of know," he said when asked about the timing of his decision. "Barring injury, I kind of knew it might be my last year, so I enjoyed every minute of it. There was a sense of accomplishment playing my last game at Assembly Hall, playing in my last (NCAA) tournament."

The early departures mean Indiana will have a very different look from the teams that won 56 games and reached the NCAA tournament's regional semifinals each of the last two seasons.

Coach Tom Crean must replace four 1,000-point scorers -- Hulls and Watford, both seniors, Oladipo and now Zeller. They were Indiana's top four scorers last season and accounted for nearly two-thirds of the Hoosiers' points.

The cornerstone, though, was Zeller, the highly-touted high school player who turned down North Carolina and Butler to lay the groundwork in Crean's grand rebuilding project.

Zeller lived up to the billing in almost every possible way. In the three years before Zeller's arrival, Crean's teams won just 28 games and didn't make a postseason appearance. With Zeller, the Hoosiers re-emerged as a Top 25 program, a Big Ten title contender and a player on the national stage. He finished with 1,157 career points and leaves as the Hoosiers' career leader in field goal percentage (59.7 percent).

But the impact he made went far deeper than any numbers.

"What Cody means to Indiana, it's much like Victor, it's hard to describe it and it's hard to put it into words, but what Cody has done has helped raise the level of every person in this program -- every coach, every player, every manager and that's not an easy feat," Crean said. "He's really come in here and left his mark on this program and it's one that will stand for a very, very long time."

Zeller is set to become the third Zeller boy to play in the NBA. His oldest brother, Luke, spent part of this season with the Phoenix Suns and his other brother, Tyler, is becoming a key cog for the Cleveland Cavaliers, who just happened to be playing in Indianapolis on Tuesday night.

Cody Zeller could have been a lottery pick last season but returned to Bloomington heavier and stronger. All he did was lead the nation's preseason No. 1 team in scoring (16.5 points), rebounding (8.1) and blocks (45) while shooting 56.2 percent from the field and 75.7 percent from the free throw line. Zeller even finished second on the team in steals (37).

But Zeller also found out how rugged life can be in the Big Ten when you're the target. Only seven Division I players attempted more free throws during the regular season than Zeller's 241 in 2012-13, and he often wound up crashing hard to the floor.

With scouts still projecting him as a lottery pick in June, Zeller made the safe choice.

"That's basketball, (injuries) can happen at any time," Zeller said. "It's part of the game, part of what goes into the decision, and that was the risk of coming back this year, too."

Where exactly Zeller falls in the draft will likely be determined on the workout circuit. Zeller said he intends to trade notes with Oladipo as the two vie to be top-10 picks and promised to finish his degree by completing two summer sessions and six credits of online work.

While athletic 7-footers such as Zeller are a rare commodity, the transition from being known around as campus as "The Big Handsome" to being just another NBA rookie comes with many potential pitfalls. Some analysts believe Zeller still needs to get bigger and stronger and must figure out how to play through contact. And should Zeller need any additional advice on what it will take to make it, he can make a couple of phone calls.

"It's a huge adjustment because you're not always the biggest and strongest. You're playing against grown men every night," Tyler Zeller said after Wednesday night's loss to the Pacers.

The youngest Zeller, Indiana's 2011 Mr. Basketball and a three-time state champ, is ready to give it a try.

"I think the guys kind of expected it," Zeller said. "The people who helped me the most, I asked them to put themselves in my shoes and asked what they would do. A lot of them, a lot of teammates told me they would go."