The 49ers have a new brief concern involving Christian McCaffrey, hence why a former Bills RB is in the picture here. The San Francisco 49ers are squeezing whatever is left out of Christian McCaffrey. But the 49ers sat McCaffrey out Monday over what became described as “tightness.” ESPN NFL insider Adam Schefter revealed who tried out for the 49ers Monday including the ex-Bills player. “Veteran RBs Nyheim Miller-Hines and Zamir White tried out for the 49ers, and RB Blake Watson visited them,” Schefter posted on the social media website X, formerly Twitter.