In 1974, the sky blue was changed to dark royal blue. The helmet was also changed to dark blue and the players' numbers were removed. Additionally, the face masks became yellow, thus making them one of the first teams in the NFL (with the Kansas City Chiefs) to use a facemask color other than the then-predominant grey. From 1978 through 1983, the Chargers wore their white jerseys at home, coinciding with the hiring of coach Don Coryell – when Joe Gibbs, a Coryell assistant in 1979–80, became head coach of the Washington Redskins in 1981, he did the same, and white at home became a Redskins staple through 2007 – but Coryell switched the Chargers to their blue jerseys at home starting in 1984. With the exception of the 1991 season and other sporadic home games since, San Diego wears its blue jerseys at home.