The person said Illinois turned its attention to Groce after Brad Stevens said Sunday he will remain at Butler. The person spoke on condition of anonymity because Illini's search is ongoing.
Illinois athletic director Mike Thomas has repeatedly declined to comment on potential replacements for Weber, who was fired on March 9. A message was left seeking comment from Ohio basketball spokesman Drew Wiseman.
Groce coached Ohio to a 29-7 record this season and a spot in the round of 16 in the NCAA tournament. The 13th-seeded Bobcats lost 73-65 to top-seeded North Carolina on Friday in one of the best games of the tournament.
Groce also helped Thad Matta take teams to the tournament as an assistant at Butler, Xavier and Ohio State.
Weber was fired at the end of a 17-15 season that included a 2-12 finish that dropped Illinois from the Top 25 and first place in the Big Ten to ninth in the 12-team conference.
Weber led the Illini to the 2005 national title game, a loss to North Carolina, but coached under heavy pressure in his final three seasons in Champaign. His last Illini team didn't make it to the post-season after a snub by the NIT and three of his last five teams didn't make the NCAA tournament.
Stevens had reportedly become an Illini target. Shaka Smart decided recently to stay at VCU.
"I am happy and extremely grateful to be the head coach at Butler University, and I am already looking forward to next season and the start of our post-season workouts in April," Stevens said in his statement.