Captain Mark Chilton urged Lancashire not to let the bitter disappointment of a C&G Trophy final loss upset their quest to win the County Championship.
Sussex, who won by 15 runs at Lord's, are Lancs' main rivals as they seek their first four-day title in 72 years.
"We could make history with three games left so we've got to put this day behind us," said Chilton.
"We felt confident of getting that total so we're bitterly disappointed we've not made it."
Chilton paid tribute to Sussex's match-winner James Kirtley but he was critical of his middle order, who dug in but were denied by Pakistani spinner Mushtaq Ahmed.
The captain himself took 59 balls over his 20 before he was stumped and Glen Chapple was caught at short leg after a 30-ball 17.
"James bowled a really good new ball spell but we thought with a couple of good partnerships we would be close," said Chilton.
"We just seemed to lose wickets at the wrong time and were never able to get on top.
"When you lose those early wickets you have to restrain yourself a bit and I was disappointed with the wickets that fell at five and six.
"If we had played for another half an hour there we would have been in a really strong position."
Lancashire have three Championship matches left, beginning with Warwickshire's visit to Blackpool on Wednesday.