Darius Lipford appears to be an intriguing candidate to join the 49ers.The former North Carolina linebacker, who went unclaimed in the recent NFL supplemental draft, was reported to have worked out for the Niners Tuesday, but did not sign with the team. But if the 49ers liked what they saw, the team could bring him aboard in the next few days or weeks of training camp.Niners rookies are due to report for camp Wednesday, a week ahead of veterans.Lipford, 6-foot-3 and 245 pounds, played 11 games as a freshman at North Carolina in 2010, then became the starter at strong-side linebacker as a sophomore. He played in all 13 games, but tore his ACL in the team's Independence Bowl game vs. Missouri. The injury forced him to sit out all of 2012, but he returned in 2013 for his junior season, appearing in 10 games.He had 20 tackles, including six for loss and 2½ sacks. He decided to forgo his final season with the Tar Heels and was declared eligible for the league's seven-round supplemental draft last week, but went unclaimed.The 49ers, of course, have a deep roster but a recent history of patience. Even if they don't see Lipford as an immediate help, the team could sign him to stash...