The San Francisco 49ers' left guard competition is finally starting to heat up. After the team started things with Connor Colby as the first-team option in the first week or two of camp, they are starting to shuffle things up, and we are seeing a different blend. Now, rookie fourth-round pick Carver Willis has returned from his concussion.

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 Competition

The 49ers also signed Doug Kramer, who will step in as the third-team center. Some of the reason is that Brett Toth, One who was the backup center, is banged up. Drake Nugent jumped from third team to the second unit, but the 49ers still needed someone to play with the third string. So, they signed Kramer.

At the same time, when Toth comes back, he could end up being more involved in the guard competition. While none of Jones, Toth, or Willis has been able to take the job from Colby, one thing is for certain, and that is that Colby is not winning the job on his own.

So, while it has just been Jones getting work with the first-team now that they have moved Colby to the right side, the other two should start to get more work with the first unit as well.

Willis is intriguing because he is a former left tackle in college. It means there has to be a transition, but at the same time, he is plenty athletic and capable of shifting inside. The 49ers' current starter at right guard was a tackle in college who kicked inside and thrived.

However, Toth is a great veteran to have. The 49ers liked his versatility, and while he has been working at center, they might want to get him some work at guard.

The player getting the most work with the first group right now is Jones. Jones was with the Dallas Cowboys last year, but did not play a single snap due to a neck injury. Before that, he did start for the Miami Dolphins. 

The preseason is going to shape this competition that appears to have only just begun.