The San Francisco 49ers begin their OTAs on Tuesday, which means we take one more step toward deciding the numerous position battles. The team has been implementing its playbook over the last few weeks, and OTAs provide a chance for more team vs. team practice sessions. It is still only helmets and shorts, but the coaches can start to see who is getting a handle on the playbook.

Since we will see the position battles move front and center, I thought I'd take some time to handicap them. We don't have a lot of useful information for this, particularly with regard to the rookies. That being said, I think it's an entertaining mental exercise. We'll start things off with a look at the offensive side of the ball.

Backup quarterbacks

Participants: Colt McCoy, Scott Tolzien, B.J. Daniels

We're off to a roaring start here with no apparent leader for the spots behind starter Colin Kaepernick. We really won't be able to do much with this until training camp. McCoy has the edge in overall veteran experience. Tolzien has two years working with Geep Chryst, Greg Roman and Jim Harbaugh, which has to count for something. B.J. Daniels was not a particularly great quarterback at South Florida, but he brings athleticism that could fit into the 49ers offense. We just need to know if he can actually complete passes at better than a 60% clip.

Leader: We don't really have a known leader, but I think Colt McCoy is most likely to end up as the No. 2 behind Kaepernick. McCoy has veteran experience, and was actually a decent scrambler at Texas. He's not a runner in the mold of Kaepernick, but he strikes me as a guy who could do some good things in the 49ers diverse offensive attack. I still think Tolzien has the edge on Daniels in part because Daniels wasn't particularly great at USF, and in part because I just don't think the 49ers unload Tolzien after two years of investment.

Backup running backs

Participants: Kendall Hunter, LaMichael James, Anthony Dixon, Jewel Hampton, Marcus Lattimore

The 49ers went into the 2012 season with what appeared to be a lot of depth at running back. Kendall Hunter was coming off a strong season, the team signed Brandon Jacobs as a short yardage option and they drafted LaMichael James as an incredibly athletic change of pace back. We actually saw something from all three running backs, but injuries split it up. Jacobs was looking solid in preseason action, bulldozing defenders in a few carries. Unfortunately an injury derailed his time with the 49ers and the preseason performance would be the highlight.

For Hunter and James, the 49ers saw both of them, but had to deal with injuries for that to happen. Hunter was playing well through the first half of the season, but a November Achilles tear sidelined him for the rest of the year. Shortly after this, James got his first opportunity, and he ran with it. He has plenty to work on, but he showed the athleticism that garnered the 49ers interest in the draft.

After that it gets interesting. Marcus Lattimore will likely be starting the season on the PUP list, and there's a better than even chance he spends the entire season on the inactive list. That would seem to leave one roster spot for Anthony Dixon or Jewel Hampton. We kind of know what the 49ers are going to get from Anthony Dixon. We have no real idea what Jewel Hampton will bring to the table. He spent most of the season on the Non-football injury list, but was added to the 53-man roster for the final five weeks of the regular season and the three games of the postseason. Clearly the 49ers like something about him. But is it enough to secure a roster spot this year?

Leader: I think LaMichael James has an early lead on this job because of the injury factor. Kendall Hunter is expected back for training camp, but until then, James gets the opportunities to push for more carries. Hunter will be one to watch once the preseason gets here. Will he be hesitant? Will he be slowed by the Achilles injury?

Those two would seem set for the top two backup spots in some form or fashion. After that, it's hard to tell. Dixon busts his butt and has the veteran experience. Hampton was a talented college back who had to recover from tough injuries before entering the NFL. Plenty will hope for Dixon to win the job, but with the multiple potential special teams additions, he enters OTAs with his roster spot seemingly no more secure than any previous year. I think Dixon could figure out a way to stick around for one more year, but it's tenuous.

Third, Fourth wide receivers

Participants: Mario Manningham, Kyle Williams, A.J. Jenkins, Quinton Patton, Ricardo Lockette, Chad Hall, Joe Hastings, Chuck Jacobs, Marlon Moore

The 49ers have plenty of talented options behind Michael Crabtree and Anquan Boldin, but it's a cluster if there ever was one. Manningham and Williams are both coming off knee injuries, although Manningham's will likely sideline him longer. Jenkins is coming off a rookie season in which he provided us with questions and no answers. Patton is a rookie with talent, but obviously is still just a rookie. Lockette is a burner, but even with his potential upside, I have to think he's looking like a victim of the numbers game.

Leader: Assuming Manningham spends the preseason and possibly some of the regular season on the PUP list, I'd say Williams is the one guy most likely to secure the third receiver spot coming out of the gate. Beyond that, there are a whole lot of question marks. Jenkins, Patton and Lockette could all surprise us, but we have little to base potential upside on at the NFL level. I'd love to see Jenkins and Patton both show up strong out of the gates in August, but there just isn't anything to say one way or another what to expect.

Second, third tight end

Participants: Vance McDonald, Garrett Celek, Cameron Morrah, Demarcus Dobbs

After seeing Delanie Walker depart for the Tennessee Titans, the 49ers added Morrah as a late free agent and then drafted Vance McDonald in the second round. Morrah is an intriguing talent, but he's never really been able to put it all together. McDonald has experience as a fairly versatile tight end in college. He spent a good deal of time split out, but will have to work on his in-line blocking.

Of course, we can't forget the returning players. First there's incumbent Garrett Celek. He operated in the third tight end role last season, providing some solid blocking. There is also Demarcus Dobbs. He is primarily a defensive lineman and special teams player, but the 49ers were intent on working him as a tight end option. He didn't get a whole lot of work at the position once the regular season began, but I imagine he'll be back competing for tight end playing time.

Leader: I gotta go with Vance McDonald, even though he's a rookie. The 49ers have proven they will sit rookies as long as they need to, but given the departure of Walker and the guys joining him in the competition, McDonald just seems like the early favorite. We'll see what OTAs and training camp bring, but I think it's a reasonable inference for now.

Center

Participants: Jonathan Goodwin, Daniel Kilgore, Joe Looney, Adam Snyder

The 49ers have a solid center in Jonathan Goodwin, and he is likely the heavy favorite to retain the job. Daniel Kilgore and Joe Looney both entered the NFL as guards, but both have been getting work at center. While it is always smart to have other options at center, I think most people view the additional work as an attempt to develop a center of the future. And we can't forget Adam Snyder. I don't think he is in a great position to win the job, but given his versatility, I think he will get snaps at center at some point leading up to the start of the season.

All that being said, with the team always on the lookout for young value to clear some cap space, I would imagine Goodwin is on the somewhat warm seat for now.

Leader: There's no doubt Goodwin has the edge at this point, but who knows what the next three months will bring. You could argue the job is not so much Goodwin's to lose as it is Kilgore or Looney's to win. I think Goodwin brings enough to the table that he sticks around one more year, but it is no gimme at this point.

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