Olson last played for the Kansas City Phantoms in the Champions Indoor Football League.
"He's a great guy. He's a guy right now that's being talked about," Harbaugh said of Kaepernick, per Conor Orr of NFL.com. "We'll just see what happens with that. Only speculation right now. He's a really good football player and like I said, I do believe he'll be playing in the National Football League this year."
Amy Trask of CBS Sports also provided her impression of owner Steve Bisciotti's thoughts on the issue:
Ryan Mallett and Dustin Vaughn are the only other quarterbacks on the roster and combined for just six pass attempts last season.
Meanwhile, Olson has even less high-level experience after throwing just three passes in his entire college career. He finished 1-of-3 for minus-1 yards at Clemson after transferring from Stanford.
Presumably, former Stanford coach Jim Harbaugh tipped off his brother, John, about his former player.
Still, Kaepernick remains unsigned despite posting a 90.7 quarterback rating in 12 games last season with 16 touchdowns and four interceptions.