Winston has started 119 of 124 NFL games, spending his first six seasons with Houston before one season in Kansas City and last season with Arizona. The move could be a sign of uncertainty about Seattle's situation at right tackle. Michael Bowie suffered a shoulder injury at the first day of camp and rookie Justin Britt is his backup.
Thomas will be reunited with Seattle coach Pete Carroll after playing for him at USC. Thomas played in 16 games last season for the Giants after being out of football in 2011 and 2012.