Offensive tackle Watson, who was born in Manchester, has joined the Denver Broncos having spent his first four years in the league with AFC West rivals, the Oakland Raiders.
Watson has battled injuries throughout his time in the professional ranks but has a better chance to be a regular starter along Denver's offensive line.
Londoner Crawford was also a free agent following a stint with the Dallas Cowboys and the 28-year-old defensive lineman has joined the Atlanta Falcons.
