Skipper Ed Joyce led by example once again as Sussex battled to avoid the follow-on against Nottinghamshire.
Joyce made his third Championship century of the season having propped up another disappointing batting display from the hosts.
Sussex reached the close on 270-8 and still need another 33 runs to avoid the follow-on having dismissed Notts for 452 in the morning.
There hopes of reaching their target of 303 to ensure they do not have to bat again rest largely with Joyce, who is unbeaten on 104, and the ability of final pair Jon Lewis (14no) and Matt Hobden to stay with him.
Chris Nash (41) and Matt Prior (30) were the only other batsmen to make significant contributions as Stuart Broad and Andre Adams both took three wickets.
The day had started well for Sussex as they took just nine overs to wrap up the Nottinghamshire innings.
The visitors added only 44 runs to their overnight score of 408-5 with Steve Magoffin claiming four wickets to finish with figures of 4-110.
Samit Patel’s fine innings came to an end when he became Hobden’s third victim of the match on his Championship debut having made 156.
Sussex’s reply got off to a dreadful start as Broad dismissed opener Luke Wells and Rory Hamilton-Brown cheaply before lunch.
Nash went on the counter-attack but perished when he slashed at a wide ball from Adams and was caught in the slips.
Prior looked in good touch in only his second Championship innings of the season but was trapped lbw by England team-mate Broad.
Luke Wright followed for 23 as he was caught behind off Adams before tea before Ben Brown was lbw to Siddle for nine.
Adams picked up his third wicket when he pinned Anyon lbw having put on 32 with Joyce and then Magoffin chipped a return catch to Patel.
While his team-mates came and went at the other end Joyce was largely untroubled as he made his half century off 99 balls and completed the 35th first class hundred of his career in a further 87 deliveries, having hit 11 fours.