The 6-foot-3, 210-pound Frost, a five-star athlete from Butler High in Matthews, N.C., originally committed to Auburn during the U.S. Army All-American game earlier this month, although there were questions about whether the Tigers would accept his commitment.
Ten days later, they finally did, according to AuburnSports.com, AuburnUndercover.com and Inside the Auburn Tigers.
Rivals, which adjusted its ratings today, ranks Frost as the No. 4 athlete in the country and the No. 20 player overall. He played linebacker and receiver in high school.
Frost originally committed to Michigan but switched after the Wolverines fired Rich Rodriguez.
He is Auburn's 18th commitment for 2011. National Signing Day is Feb. 2.
Here's an updated list of Auburn's commitments (star ratings are by Rivals):
- Angelo Blackson, DL, 6-5, 289, 3-star, Bear, Del. (Red Lion Christian Academy)
- Quan Bray, ATH, 5-11, 178, 4-star, LaGrange, Ga. (Troup County High)
- Brent Calloway, RB/LB, 6-1, 210, 5-star, Russellville, Ala. (Russellville High)
- Sammie Coates, WR, 6-3, 170, 3-star, Leroy, Ala. (Leroy High)
- Jaylon Denson, WR, 6-3, 190, 4-star, Hoover, Ala. (Hoover High)
- Reese Dismukes, C, 6-3, 272, 4-star, Spanish Fort, Ala. (Spanish Fort High)
- Kiehl Frazier, QB, 6-3, 215, 4-star, Springdale, Ark. (Shiloh Christian)
- Kris Frost, ATH, 6-3, 210, 5-star, Matthews, N.C. (Butler High)
- Justin Garrett, OLB, 6-2, 185, 3-star, Tucker, Ga. (Tucker High)
- Keymiya Harrell, DE, 6-5, 235, 3-star, Plantersville, Ala. (Dallas County High)
- Chris Landrum, LB, 6-2, 215, 3-star, Sweet Water, Ala. (Sweet Water High)
- JaBrian Niles, DE, 6-2, 270, 3-star, Mobile, Ala. (Davidson High)
- Thomas O'Reilly, OL, 6-3, 315, 3-star, Marietta, Ga. (Pope High)
- Greg Robinson, OL, 6-5, 296, 4-star, Thibodaux, La. (Thibodaux High)
- Jonathan Rose, CB, 6-2, 170, 4-star, Leeds, Ala. (Leeds High)
- Anthony Swain, S, 6-3, 215, 3-star, Gadsden, Ala. (Gadsden City High)
- Robenson Therezie, DB, 5-10, 180, 4-star, Miami, Fla. (Jackson High)
- C.J. Uzomah, TE/HB, 6-5, 230, 3-star, Suwanee, Ga. (North Gwinnett High)