INDIANAPOLIS (AP) — Indiana assistant Rob Senderoff resigned Tuesday amid a telephone recruiting scandal that already has cost the Hoosiers one basketball scholarship and coach Kelvin Sampson a $500,000 pay raise.

The NCAA is still conducting its own investigation, which could lead to further sanctions.

"It's a very strong message," athletic director Rick Greenspan said of the internal investigation and report to the NCAA. "It's been delivered by voice, by written word, by action. If you look at the self-imposed sanctions and the corrective actions, an astute person would look at these as very significant ... all the way down the line."

The report, which does not accuse Sampson of any direct NCAA violations, details more than 100 impermissible recruiting calls, most of them by Senderoff. At least 10 of them were three-way calls that Sampson had been patched into, and another eight included incoming calls that couldn't be identified.

Greenspan wouldn't speculate what action the NCAA would take or the timetable for reaching a decision. He said Dan Dakich, a former Indiana player and assistant coach and former head coach at Bowling Green, would likely take Senderoff's spot on Sampson's staff.

Dakich was hired as IU director of basketball operations in June and would be subject to the same restrictions the university imposed on Senderoff, Greenspan said.

Senderoff, a former assistant at Kent State, was hired by Sampson in May 2006, the same month the NCAA sanctioned Sampson for making 577 impermissible phone calls between 2000-2004 while he was coach at Oklahoma. Sampson was barred from calling recruits or making off-campus recruiting trips for one year, but on Oct. 14, less than five months after those sanctions expired, Indiana announced its compliance office had discovered the new violations that occurred while the original sanctions were still in effect.

"It's important to keep this in perspective," Greenspan said. "The total number of calls at issue is a fraction of 1 percent of the total number of recruiting calls made each year by the men's basketball staff. We take this matter very seriously and demand full compliance with the rules.

"We believe these sanctions more than compensate for the extra calls," he said.

The three-way calls with recruits normally are permitted under NCAA rules but were banned as part of the previous sanctions.

As a result of the internal investigation, Indiana gave up one basketball scholarship in 2008-09 and Sampson, starting his second season with the Hoosiers, voluntarily forfeited his scheduled pay raise. Also, Senderoff forfeited a scheduled pay raise and was banned from calling recruits and making off-campus recruiting visits for one year.

Also among the corrective actions Indiana proposed in its report to the NCAA infractions committee were letters of reprimand to Sampson, Senderoff and assistant coach Jeff Meyer, who made at least four impermissible calls, and attendance at biweekly compliance meetings for Sampson and the rest of the coaching staff for one year. Sampson, Meyer and assistant coach Ray McCallum also would be required to attend a 2008 NCAA rules seminar.

The university also agreed to stop recruiting one player who was the subject of 25 of the NCAA violations. The identities of that player and 13 others who received impermissible calls were redacted from the Oct. 3 report to the NCAA, which was released Tuesday following a Freedom of Information Act records request to IU.

"The corrective actions as well as self-imposed sanctions were put in place when we filed this report," Greenspan said. "Subsequent to this filing, Rob has decided it's in his interest and university's best interest to resign. ... We're prepared as a department, as a university, as a staff to move forward."

After the findings of the Indiana investigation were disclosed earlier this month, Sampson said he wasn't aware that nine of the 10 calls were three-way connections. The one he knew was a three-way call was to clear up questions from a recruit who had already committed to making an on-campus visit, he said.

Under the university's sanctions, Sampson would be restricted to four off-campus recruiting days during the fall 2007 contact period and no more than 10 additional off-campus recruiting days through July 31, 2008.