The two go back a ways, as seen in this piece from ProstAmerika. Nice research work.
I was able to get in on a conference call with Kasey Keller and Angel, the New York Red Bulls’ designated player and captain.
“He’s obviously a quality goalkeeper,” Angel said of Keller. When the conference moderator said Angel had to step away to catch the team plane to Seattle, Keller joked, “No you don’t.”