The 49ers have brought in a fourth quarterback. San Francisco announced on Wednesday that the club has signed Adrian Martinez to its practice squad. Martinez has bounced between the 49ers practice squad and 53-man roster this season before a quick stint last week with the Jets' practice squad. He briefly appeared in one game for San Francisco to take a knee to cap the team's Nov. 2 victory over the Giants. Martinez's signing gives the 49ers four quarterbacks in their building, with Mac Jones behind starter Brock Purdy on the 53-man roster and Kurtis Rourke on the reserve/non-football injury list.
More info on: Mac Jones, Brock Purdy, Kurtis Rourke