The Ravens want to make their bird baths a little safer. The greatest swimmer of all time is here to help. Michael Phelps agreed to help Baltimore's players learn how to swim after an Instagram appeal from star cornerback Marlon Humphrey and some teammates: A post shared by Marlon Humphrey (@marlon) "Hey Mr.

Michael Phelps, the most decorated Olympian of all time, certainly knows a thing or two about swimming techniques.

The Baltimore Ravens are calling in the big guns... to teach them how to swim? Legendary Olympic swimmer Michael Phelps says he will provide lessons to his hometown NFL team, which posted a plea for his help and claimed that a third of its players—around 17—never learned how to swim.