Complex sentence: Palmer then launched one of his patented charges with birdies at 9,11, and 12 to close within one, but a three-putt bogey at 13 proved to be costly for Palmer.
Split into simpler sentences: Palmer then launched one of his patented charges with birdies at 11 and 12 to close within one. A three-putt bogey at 13, however, proved to be costly for Palmer.