Pretty sure the last E is correct. It is the second letter from the clue, Firstly, the F1 Champion = JENSON, which also fits the rest of the crossword in that area!
I wondered if the clue was more cryptic and was from shooting or archery where a nervy shot would hit the edge of the target?
Thanks, Jumbuck, I was thinking more along the lines of the role of the scrum half! Does that make 33(d) STOP then? Then I am done! Although, I went for ADEPT rather than AGENT for 57 (a) but I think AGENT fits the clue better!