Center fielder Jung Hoo Lee will undergo an MRI exam on his tight back on Monday, a concerning development for the Giants as they enter the final week of Cactus League play. Lee was slated to start Saturday’s game against the Mariners,

The Giants announced on Monday morning that Lee will undergo an MRI later in the day as the center fielder deals with mid-back tightness. Lee will have a follow-up with team orthopedist Ken Akizuki for another exam, as well. “It hasn’t gotten any better,” said manager Bob Melvin. “Send him in, get an MRI, see what’s there.”

The San Francisco Chronicle reported Tuesday (U.S. local time) that an MRI on Lee's tight back did not reveal any structural damage. Although there is no timetable yet on his return, the South Korean player will not likely miss an extended period of time.