49ers free-agent report: Josh Johnson

The San Francisco 49ers have 15 potential unrestricted free agents who would hit the market when the new league year begins on March 10. Let’s continue our countdown with a look at another backup quarterback.

QB Josh Johnson

A fifth-round pick of the Tampa Bay Buccaneers out of the University of San Diego -- where he played for Jim Harbaugh -- in 2008, Johnson spent three years with the Buccaneers and one each with the Cleveland Browns, Cincinnati Bengals and Niners. He has started five of the 29 games in which he’s played in his career and is 0-5. Johnson has played in three games since the start of the 2012 season but has only started one since his rookie season. His career QB rating is 57.7.

49ers career: Johnson actually spent the 2012 offseason with the Niners before returning last May. But he was never active and was actually released and re-signed on three separate occasions.

Argument for keeping Johnson: Like fellow backup QB and pending UFA Blaine Gabbert, Johnson is already well-accustomed to the Niners’ offense. So Geep Chryst's promotion from QB coach to offensive coordinator should give Johnson a head start on any other quarterback coming to Santa Clara to back up Colin Kaepernick. Plus, his skill set more closely resembles that of Kaepernick’s, so why not?

Argument for letting Johnson walk: He never appeared in a game for the Niners so where’s the value, besides being a scout team QB during the week?

Bold prediction: Johnson is tied so closely to Harbaugh, and his contributions might not be seen as that crucial by the new staff, that it is tough to see Johnson returning to Santa Clara.