The Dallas Cowboys have been known throughout their history as having outstanding Offensive Linemen, and John Niland was the first one they acquired with a first round pick (5^th Overall in 1966).  

John Niland won the starting job at Left Guard for good in his second season in the NFL (1967) with the Dallas Cowboys, and would then go on to stake a claim as one of the elite Offensive Guards in the National Football League.  Niland would be named to the next six Pro Bowls and landed a pair of First Team All-Pros in the process (1971 & 1972).  The former Iowa Hawkeye would win a Super Bowl with the Cowboys in Super Bowl VI, and his upper-echelon blocking played a large part in that historic championship.