Phillips, who played in three games as a redshirt freshman in 2014, was expected to compete with redshirt freshman Drew Barker and junior Patrick Towles for the starter's job this spring under new offensive coordinator Shannon Dawson, but the Tennessee native ruptured his Achilles tendon during team workouts on Wednesday.
"He had an Achilles tendon injury in workouts this morning and will have surgery," said UK football spokesman Tony Neely. "He'll miss the spring, but we're hopeful he'll be able to play this season."
Neely added there's no timetable on his recovery. "It will be determined by how his rehabilitation goes."
It's been an eventful off-season for UK quarterbacks. Senior Max Smith elected to transfer to San Diego State, and Barker was involved in a well-publicized altercation in Richmond, Ky., with teammates Dorian Baker and Tymere Dubose involving an Eastern Kentucky University player who was hospitalized. No charges have stemmed from that incident, but UK head coach Mark Stoops acknowledged that his players had been questioned by authorities.
Towles, who started 12 games for UK last season, likely begins spring No. 1 on the quarterbacks depth chart. The 6-foot-5, 238-pound Kentucky native threw for 2,718 yards and 14 touchdowns with nine interceptions, showing glimpses of his potential with a 390 yards passing, 76 yards rushing and four touchdowns against Mississippi State, as well as a 369-yard, three-touchdwon performance in a near upset of Florida.
The 6-3, 216-pound Barker, who was one of the Bluegrass State's elite prospects in the Class of 2014, passed for 2,671 yards and 34 touchdowns as a senior at Conner High School.