Washington Redskins offensive lineman Mike Williams, who overcame weight problems to become a valuable member of the unit in his first season with the team, is expected to miss the 2010 season because of blood clots near his heart, two people familiar with the situation said late Friday night. Williams, projected to compete for a starting spot at right guard, was hospitalized recently because the problem, the team sources said. Although Williams has been released from the hospital, the organization is concerned that his condition could be career-threatening and likely will keep him off the field for at least the upcoming season, which gets underway July 29 when the team begins its first training camp under Coach Mike Shanahan.