The San Francisco 49ers have signed offensive lineman Alex Boone to a contract extension through the 2015 season.
General Manager Trent Baalke said in a statement Thursday that the 49ers are ''pleased with the progress'' Boone has made since the former Ohio State lineman joined the franchise as an undrafted free agent in 2009. Baalke also said Boone ''is a great example of what hard work, dedication and focus can do to further a young player's career.''
Boone is a reserve on San Francisco's offensive line but is among a seven-man rotation that sees considerable playing time. He spent 2009 on the practice squad, was inactive until the final game last season and has played in all 12 games this year - mostly in short-yard situations and on special teams.