Tasked with scoring 436 on the final day with nine wickets in hand, Notts withstood early pressure from Glamorgan to earn a draw at Sophia Gardens.
Lyndon James and Joe Clarke batted through the entirety of the second session after the losses of Matthew Montgomery and Ben Slater.
The latter was eventually dismissed for 95 with the first ball after tea, while James faced 192 balls for his unbeaten 76.
Steven Mullaney offered valuable to support to the young all-rounder with an 81-ball vigil of his own, with Notts four down when the sides shook hands with 11 overs remaining.