Langer, who improved his overnight lead with three birdies on the front nine, made two bogeys and a double-bogey on 15, 16 and 17 to fall three strokes back heading into Sunday's final round.
Morgan turned in a 7-under 65 and Jenkins had a 67 to share a one-stroke lead at 10-under 134.
Mike Goodes (68) and Jerry Pate (71) share third place at 9-under 135 and former Masters champion Larry Mize (69) and 2007 Allianz champion Mark James (69) lead a four-way tie at 136.
Britney Spears debuts 'Perfume' video
Wisconsin business offering 'therapeutic cuddling' forced to close