As he awaits a ruling on his eligibility, Kansas freshman Cheick Diallo has hired an attorney with experience battling the NCAA on student-athlete rights issues, Yahoo Sports has learned.

Attorney Don Jackson was formally hired Monday to join Diallo's legal team, which has become worried the NCAA could delay a ruling this season, sources told Yahoo Sports.

Check Diallo was MVP of the 2015 McDonald's All-American game. (AP) More

Jackson has represented former McDonald's All-Americans Marvin Stone and Jackie Butler in amateurism investigations, and this year served as a lawyer in Austin Nichols' successful move from Memphis to Virginia amid the NCAA's initial transfer restrictions.

Diallo, a projected high-lottery pick in the 2016 NBA draft, had remained hopeful of a ruling by Tuesday when Kansas plays its final preseason game. Nevertheless, the way the NCAA has pushed the investigation days before the start of regular season has given Diallo's camp serious pause about his status this season. Should the NCAA prolong its investigation beyond Tuesday, Diallo plans to give Jackson clearance to use Kansas' case information and battle for a final decision, sources said.

The NCAA has held an extensive investigation into Diallo. Diallo, 19, was expected to give Kansas another talented player in the frontcourt to compete as one of the best teams in the nation. At 6-foot-9, he has intrigued several NBA teams.

Diallo was named MVP of the McDonald's All-American game in March after posting 18 points and 10 rebounds. He also won co-MVP of the Jordan Classic game with Arizona's Allonzo Trier.

NCAA officials have investigated the legitimacy of Diallo's past schooling and curriculum. Diallo attended middle school in Mali before transferring to Our Savior New American in Centereach, N.Y., as a ninth grader. Our Savior has had graduates accepted into top universities across the country.

The NCAA received 2,000 pages of homework from Diallo's Our Savior high school courses, and has requested middle-school transcripts as far back as sixth grade, multiple sources told Yahoo. In 2014, Mike Nzei was ruled ineligible at Seton Hall after being unable to produce his homework from Our Savior.

Diallo is in his second academic semester at Kansas.

Diallo and Kassoum Yakwe of St. John's attended Our Savior together. Yakwe also is waiting for an eligibility ruling. Along with Diallo's Mali and New York schools, the NCAA has investigated his legal guardian Tidiane Drame, multiple sources told Yahoo. Drame has hosted basketball camps in Mali since 2007, become known among high school and college coaches and started the "Mali Hope" program that has given African basketball players an after-school structure.

Kansas coach Bill Self has called the eligibility process with Diallo "frustrating" but told reporters on Monday that the university will not publicly campaign for a favorable result for him.

Kansas begins the regular season at home against Northern Colorado on Friday and faces Michigan State on Tuesday.