Beckham said he felt the injury while taking swings in the batting cage on Friday. He said the team considers it a ''mild tweak'' but will give the 27-year-old Atlanta native seven days off.
He said with rest it should be fine for opening day.
Beckham is the second White Sox player to suffer a left oblique strain this spring training. Right-hander Matt Lindstrom is working his way back to action after the setback two weeks ago.