Asa Jackson has a unique claim among 49ers cornerbacks.
At 5-10, he's the only player under 6-1 who played outside cornerback for San Francisco in 2017. He played exactly one snap there in a Week 4 loss to Arizona when Rashard Robinson briefly left the field with an injury.
The others who played the position last season all had the height and long arms typical of a cornerback in the Seahawks'-like, press-coverage defense: Dontae Johnson (6-2); Ahkello Witherspoon (6-2); Robinson (6-1); Greg Mabin (6-1) and Tyvis Powell (6-2).
All of which ought to serve as a guideline for which cornerbacks the 49ers are most interested in during free agency and the draft.