Lee underwent an Anthogram MRI and a team physician noticed "little to no changes" in the elbow area. The MRI will be reviewed for a second opinion by Dr. James Andrews.
Lee will likely resume throwing Monday, the team said, but will forego his next scheduled start on Tuesday. His next start is listed as "TBD."
The 36-year-old left-hander has battled elbow injuries in each of the past two seasons that have limited his appearances.
He threw only 81 and 1/3 innings in 2014, going 4-5 with a 3.65 ERA.
The four-time All-Star is slated to begin his sixth season with Philadelphia this year.
- Will Green