He still hasn't given his Butler teammates a definitive no, either.
The 6-foot-9 sophomore announced Wednesday he would enter the draft but planned to keep open the possibility he might return to the school he nearly led to a national championship.
Hayward has until May 8 to withdraw his name from the draft, though he is projected to go in the top 15 picks and would become the first Butler player selected in the first round.
"I have decided to declare for this June's NBA draft," Hayward said in a statement released by the school. "At the present time, I have not signed with an agent. I'm looking forward to further exploring my options in the NBA, while finishing this semester strongly in the classroom."
Hayward was seen smiling inside the basketball office Wednesday afternoon as he chatted with two of his teammates - outgoing seniors Avery Jukes and Willie Veasley - before the decision was announced. Jukes and Veasley were scheduled to play briefly with the Washington Generals in a Wednesday night game at Conseco Fieldhouse against the Harlem Globetrotters.
A native of Brownsburg, Ind., Hayward led the Bulldogs with 15.5 points per game and into the school's first national championship game. He was voted Horizon League player of the year and Most Outstanding Player of the West Regional, and along the way his draft stock soared.
Hayward is considered a small forward with point-guard skills, a combination that made him a matchup problem for most college teams. At Butler, Hayward handled the ball, shot 3-pointers and became even more adept at driving past bigger defenders who struggled against Hayward's smooth moves and uncanny body control around the basket.
His versatility was one of the primary reasons Butler reached the Final Four for the first time.
And Hayward had two chances to give the Bulldogs a national title. But he missed a baseline jumper with about 5 seconds to go, and his buzzer-beating half-court heave rolled off the rim, giving Duke a 61-59 victory.
Butler coach Brad Stevens sounded as collected about the decision as he had throughout the Bulldogs' improbable tourney run.
"We'll support him as we gather additional information," Stevens said, one week after signing a 12-year deal to stay at Butler.
Stevens' decision left only one lingering question for the Bulldogs: Would Hayward return?
He still could, and if Hayward pulls out of the draft, Butler will have four of its five starters back. Some believe that could put the Bulldogs among the top five in the preseason poll.
Without him, Butler will still have 2008 Horizon League player of the year Matt Howard and both guards, Ronald Nored and Shelvin Mack, back in the lineup. Nored was chosen the league's co-defensive player of the year this season.
And an NBA team will have a new millionaire cornerstone for the future.
The announcement came on the same day two other players from Indiana, Purdue center JaJuan Johnson and Purdue guard E'Twaun Moore, announced they will enter the draft but will not sign with an agent, either.