Michael Phelps taught several of the Baltimore Ravens how to swim after the team asked the 28-time Olympic medalist to coach them last month

Phelps also toured the smaller pools at the Ravens' facility, and he spoke to the team on the practice field along with former Ravens star Ray Lewis.

In a social media video, Ravens Marlon Humphrey, Ronnie Stanley, Kyle Hamilton and Charlie Kolar invited Phelps, a Baltimore native and longtime Ravens fan, to visit their training camp. They said that one in three Ravens players could not swim.