Angus Robson made 82 but only 42.1 overs were possible on day three at Lady Bay to ensure the Second XI Championship match finished as a draw.
Resuming the days play on 40-0 from 19 overs, County were still 80 runs in arrears. Robson and Adam Waite took their partnership to 73 before Waite was dismissed in the 31st over.
In trying to pull seamer Brett Hutton, Waite got a top edge and was caught by Luke Wood running in from the third man boundary. Waite made a patient 26 from 81 balls.
Harry Bush joined Robson, and the pair looked comfortable against the Nottinghamshire seam attack. Robson moved to his 50 (121 balls, 5x4) in the 36th over, his second 50 of the match.
The partnership had added 45 when Bush 9 (40) was out lbw trying to sweep spinner Adam Tillcock in his second over. Robson was continuing to prosper and found the ropes on a further five occasions after reaching 50.
With the sky becoming darker, Robson finally went in the 57th over, caught at deep point by Nick Langford when cutting spinner Sam Wood. Robson had made a fine 82 from 186 balls, and will no doubt have been very disappointed to have missed out on a well-deserved century.
The score was now 134-3 and only a further four overs were possibly before rain drove the players from the field. Ben Raine 10 (42), and Tom Wells 8 (19) were the not out batsmen. County ended on 143-3 off of 61.1 overs, a lead of 41.
The players came off for rain at 2.12pm and an early tea was taken. The umpires called a halt to proceedings just before 3.30pm so Nottinghamshire took 10 points and Leicestershire 9.