General manager Trent Baalke perhaps supplied some insight Wednesday into the 49ers' plan after Frank Gore is no longer the every-down running back.

"I'm a big believer -- we are big believers -- in a three-headed approach," Baalke said. "In other words, having a group of backs that bring to the table something a little bit different than the other one so you can do a lot of different things. But also having those backs be able to do enough things the same so you don't become so predictable on game day."

Gore, 29, who rushed for 1,214 yards and eight touchdowns last season, is under contract for two more seasons. Kendall Hunter is expected to return to full strength for the season after undergoing season-ending surgery to repair a partially torn Achilles tendon. And the 49ers selected LaMichael James last season with a second-round draft pick.

"All three of our backs can run the full gamut of our offense," Baalke said. "But they also bring something unique to the table, different styles, so it's very difficult when you're a defense to look out there and say, 'OK, they're going to do this or they're going to do that.' But then they also have to deal with the different running styles."

Baalke said the 49ers never want to get into a position in which they much fill holes atop the depth chart with players from that year's draft class. The 49ers do not necessarily have a need at running back in next week's draft. Anthony Dixon and Jewel Hampton also return from the 49ers' 53-man roster of last season.