Despite a testing opening courtesy of pace bowlers Pennington and the fit-again Olly Stone, Nottinghamshire’s only breakthrough in the first hour came when Paterson had Luke Wells caught at second slip.
Lyndon James dismissed Josh Bohannon immediately before lunch to end a threatening partnership with Jennings, and Nottinghamshire emerged with renewed energy.
But Jennings, having built a 128-ball half-century, upped the tempo as a paddle sweep for four and a straight six off Calvin Harrison’s leg spin had him set for a second hundred of the season.
Nottinghamshire’s bowlers fought back as Jennings top-edged a reverse sweep against Harrison to slip, where Tom Moores took an easy catch, and Balderson was beaten for pace by Stone, hit squarely in front as he tried to flick across the line.