Locksley is the fourth candidate who has reportedly interviewed for the job, along with former Oakland Radiers coach Lane Kiffin, Oklahoma defensive coordinator Brent Venables and Virginia Tech defensive coordinator Bud Foster.
Several media outlets had reported that Clemson athletic director Terry Don Phillips flew to Detroit on Nov. 7 to interview Kiffin, but a source confirmed Phillips went there to interview Locksley. Illinois played Western Michigan in Detroit that weekend.
Locksley is in his fourth season as offensive coordinator at Illinois. A 17-year coaching veteran, he previously was running backs coach and recruiting coordinator at Florida under Ron Zook, with whom he works at Illinois.
Clemson interim coach Dabo Swinney is also considered a candidate for the Clemson position, which opened when Tommy Bowden resigned earlier this season after a disappointing start.
Clemson (5-5, 3-4 ACC) travels to Virginia this week and closes its regular season on Nov. 29 against its in-state archrival, South Carolina. Illinois (5-6, 3-4 Big Ten) is at Northwestern on Saturday.
Phillips has said he hopes to make a hire within seven to 10 days after the end of the regular season.
Heather Dinich covers the ACC for ESPN.com.