The common thinking was Craig Dahl – the veteran – would man the back of the secondary until Eric Reid was ready to take over. But that hasn't been the case so far in training camp. C.J. Spillman, known for his special teams work, has gotten reps with the first team at free safety.
"I see myself as more than just a special teams player," Spillman said after Tuesday's practice. "I see myself as a defensive player. I'm trying to get myself in position so when an opportunity comes along like it is now I can just take advantage of it. Grab the bull by the horns."
Spillman joined the 49ers in 2010 when he was claimed off waivers and has since been a key contributor on punt and kickoff coverage. He earned the team's Blue Collar Special Teams Player of the Year award last season after coming into the NFL with the Chargers as an undrafted free agent out of Marshall in 2009.
He combined for 50 special teams tackles since joining San Francisco Oct. 12, 2010.
"(Spillman) is coming along as a safety. I know he's got the moniker that he's a special teams player only, but he's capable of playing a solid safety position in the NFL," defensive coordinator Vic Fangio said.
"He just has to become solid in his assignments and techniques because you know back there if you make a mistake it could be a big one. If a D-lineman makes a mistake, maybe it's a six or ten-yard gain. Back there it could be a home run."
Fangio said he plans to rotate free safeties with the first team every two or three days as training camp progresses, but notes Spillman's tenure as a possible reason to why he was allowed to run with the first team ahead of Dahl and Reid.
"At the end of the day football's football. Regardless of how long you play. It's just getting back to the game of football. Here it's just the terminology," Spillman said.
While Dahl and Reid are likely to emerge as favorites to earn the starting job at free safety as they become more familiar with the scheme, nothing is a certainty and the competition is still up in the air.
Spillman isn't bothered by the idea of competing for a job with a first-round pick in Reid.
"Regardless of first round or not. Competition is competition," he said. "So don't count out anybody regardless of first round or undrafted. Never underestimate anybody's potential."