Marcus Lattimore’s first pre-draft contact from the 49ers didn’t come from a scout, assistant coach or general manager Trent Baalke. Instead, it was from running back Frank Gore, who called the South Carolina star a few days after he sustained a horrific knee injury in late October. At the time, Lattimore, one of college football’s most electrifying tailbacks, wasn’t sure he’d ever play again after tearing three of the four major ligaments in his right knee, which was also dislocated. Gore, who tore the ACL in both of his knees in college, offered support. “He’s just told me to keep that positive mindset and that’s what I’ve been doing these past five, six months,” Lattimore said. “And I feel like that’s why I’m doing so great with my rehab.” On Saturday, six months to the day after his injury, Lattimore was selected in the fourth round of the draft by the 49ers, who can afford to ease him into the NFL. San Francisco’s stacked backfield is headlined by Gore, a Pro Bowler who has two capable caddies in LaMichael James and Kendall Hunter. It’s not clear what, if any, contribution Lattimore will make as a rookie. On Saturday, though, he was just thrilled to count Gore as both a teammate and inspiration. His once-tenuous NFL dream had been realized. “Right after it happened I doubted myself — I did do that and I lost hope,” Lattimore said. “But one of my good friends came over, I got a chance to talk to Frank Gore, I got a chance to talk to (Broncos running back) Willis McGahee and I realized God doesn’t make mistakes. He did everything for a reason and he put me in this situation. Now I’m with the 49ers. It’s just a great, great situation for me.”