Deron Williams scored 23 points and the Nets escaped with a 97-94 victory on Wednesday night after Milwaukee's Monta Ellis missed a chance to tie the game with three foul shots in the final seconds.
Paul James's charge-down of Harry Ellis's kick nearly gave the Ospreys a dream start to the second half, but Leicester got themselves out of a corner and stayed nine points clear until Hook's penalty, which came just after Flood limped off.