By now, every 49ers follower knows the team's biggest needs in the draft – cornerback and wide receiver.But over the three-day selection process that begins May 8, the Niners no doubt will select at least one player to challenge for playing time at another position of need: center.With the departure of veteran Jonathan Goodwin, an unsigned free agent who started the past three seasons in San Francisco, Adam Kilgore is expected to inherit the position.Kilgore, Goodwin's primary backup last season, is the front-runner to earn the job, with another veteran, Adam Snyder, capable of backing him up. Snyder can play both guard and center, as can another player on the roster, Joe Looney. Also on the 49ers roster is Ryan Seymour, who also has some experience at the position from his college days at Vanderbilt."I feel good about that group competing for that spot," 49ers general manager Trent Baalke recently told Matt Barrows of the Sacramento Bee.But with 11 draft choices available, the 49ers are expected to draft at least one player to challenge that group.In his latest mock draft, Todd McShay, an NFL analyst for ESPN, has the Niners using their No. 1 pick (30th overall) on TCU...