Cromartie, 26, originally signed on with the Chargers as an undrafted free agent out of Wisconsin back in 2013. He lasted just over one season with the Chargers before signing on to the 49ers’ practice squad during the 2014 season.
San Francisco declined to tender him a restricted free agent offer this offseason, making him an unrestricted free agent. The Bills elected to sign him to a contract several months ago before cutting him loose shortly after this year’s draft.
Cromartie later signed on with the Seahawks but was placed on injured reserve coming out of the preseason and eventually released with an injury settlement.
In 2016, Cromartie appeared in 10 games and recorded five tackles and no interceptions for the 49ers.
Ervin, 23, is a former fourth-round pick of the Texans back in 2016. He’s currently in the second year of his four-year, $2.887 million contract and stands to make base salaries of $540,000 and $630,000 over the next two years of the agreement.
In 2017, Ervin appeared in four games and rushed for 12 yards on four carries to go along with eight receptions for 38 yards receiving and no touchdowns. He also contributed 93 kick return yards and 60 punt return yards.