Martin appeared in nine games for the New England Patriots last year, catching 24 passes for 269 yards and two touchdowns. The 26-year-old also displayed value as a return man, averaging 11.5 yards on eight punt returns and 25.7 yards on 10 kick returns.
Martin isn't an ideal addition for San Francisco, but the 49ers aren't in a position to be picky. Through three games, only Torrey Smith and Jeremy Kerley have 100-plus yards receiving. Quinton Patton is third on the team in receiving yards (93) and has nine catches.
The San Jose Mercury News' Tim Kawakami commented on how bad things are with the 49ers offense:
Tim Kawakami @timkawakami
I've never heard of Keshawn Martin but I'm pretty sure he's now the 49ers' third-best receiver.2016-9-27 19:10:59
The San Francisco Chronicle's Eric Branch highlighted what is a major source of the team's current problems:
Eric Branch @Eric_Branch
#49ers have used 2 of their 15 top-100 draft picks since 2013 on skill-position players: (RB Hyde, TE McDonald).2016-9-27 19:07:18
Martin's presence gives San Francisco another option in the passing game, which is certainly needed. At the same time, expecting him to make a significant difference for the 49ers is unrealistic.
Not only does he lack a strong track record as a pass-catcher, but he also can't do anything to solve the team's problems at quarterback. Starting Blaine Gabbert is a recipe for disaster, and Colin Kaepernick is unlikely to be any better based on his struggles last year.
With the NFL's new kickoff rule leading to more return opportunities, having a capable return man can be a nice asset, though, and Martin could help in that regard.