"It's been bothering him enough and bothering me enough, frankly, to go ahead and precautionary do that," general manager Ruben Amaro Jr. said of the MRI that was taken Saturday.
"Rather than really pushing him early, we're going to kind of take it easy on him so there are residual effects throughout the year."
Utley has been taking regular batting practice. His knee becomes painful in explosive baseball movements, such as running and fielding.
The Phillies do not have a definitive timetable for when they expect Utley to play in a spring training game.
MARLINS: Florida slugger Mike Stanton left the team's exhibition opener against the Miami Hurricanes after straining his right quadriceps while trying to beat out a groundball.
Stanton fell to his knees after crossing first base, then rose and limped off the field before riding a cart from the dugout to the clubhouse.
Stanton hit a two-run homer in the first inning.
TIGERS: Miguel Cabrera will be in the Detroit's lineup for the first time this spring as a designated hitter in today's exhibition game against the New York Yankees.
Cabrera missed the first week of camp after being arrested for suspicion of driving under the influence of alcohol Feb. 15 near Fort Pierce, Fla.
Cardinals: Right fielder Lance Berkman says his left elbow is sore, but he'll still play in today's spring training opener against Florida.
The elbow on Berkman's throwing arm began hurting during the off-season as tried to strengthen it in preparation for the move from first base to the outfield.
INDIANS: Cleveland outfielder Shin-Soo Choo sat out the spring training opener against Cincinnati because of a sore left elbow.
Choo says he recently had an MRI, which showed no structural damage in the elbow.
GERUT RETIRES: Outfielder Jody Gerut, 33, is retiring after six seasons in the majors.
He appeared in 574 games with the Indians (2003-05), Cubs (2005), Pirates (2005), Padres (2008-09) and Brewers (2009-2010).