What jersey number did Steve Young wear with the 49ers?

What jersey number did Troy Aikman wear with the Cowboys? What position did Steve Young primarily play? Steve Young is best known for playing with which NFL team? Which college was Steve Young playing for when he entered the NFL? What position did Jim Kelly primarily play? Which college was Jim Kelly playing for when he entered the NFL? What jersey number did Jim Kelly wear with the Bills? What position did Warren Moon primarily play?