The San Francisco 49ers' left guard competition is finally starting to heat up. He did not get mixed in with the starters yet, but Willis did immediately jump in with the second-team at left guard. The 49ers elected to push Colby to right guard and let Robert Jones, who had been getting work with the second team, jump in with the ones. Carver Willis Joins San Francisco 49ers Left Guard CompetitionThe 49ers also signed Doug Kramer, who will step in as the third-team center. The 49ers' current starter at right guard was a tackle in college who kicked inside and thrived.