San Francisco commuters will get a beginning-of-the-work-week gift Monday when the portion of Fremont Street that passes under the damaged Transbay Transit Center will open to traffic, Transbay officials said Sunday.

The opening of Fremont, between Howard and Mission streets, comes nearly three weeks after cracks were found in steel beams above the motorway. The street was originally supposed to open on Friday, but officials ordered a delay while workers bolstered the structure below the two fractured beams.