I think it was Shareef Miller who beat him on consecutive plays by going outside and underneath. Replay the tape, after the second one you'll see Franklin with a frustrated expression on his face mouthing the word "Jenkins" directly after (pretty good at lip reading
).
Unfortunately, I think he is one of those players Franklin refers to when he mentions "certain players just don't respond when the lights come on". Just my 2 cents (and a little tin hat I know) but I'm pretty good at reading people. His body language is not good when he screws up or has a sub-par play. The good ones visibly get upset with themselves.....Jenkins just sort of hides.
Like I said, just my two cents, but I don't think Jenkins will ever be the player we envisioned. Wright is a much better player and we probably have 4 other tackles that are better (Bates, Mahon, Nelson, Fries). Can't see a light there which is disappointing, after this year he may be a transfer candidate.