Clay C. Christiansen (born June 28, 1958) is an American former Major League Baseball pitcher.

In addition to being an American Legion baseball standout, he was the quarterback of the football team, played basketball and participated in track and field.

Christiansen is married to local Kansas City sportscaster Karen Kornacki.

He currently works for Pepsi in Olathe, Kansas as an install driver for the vending department.

This biographical article relating to an American baseball pitcher born in the 1950s is a stub.