Derbyshire 207 for 4 (du Plooy 66*, Reece 57) beat Birmingham Bears 203 for 7 (Hain 79, McKiernan 3-39) by six wickets
After the Bears piled up 203 for 7, du Plooy smashed an unbeaten 66 from 25 balls to see his side to 207 for 4 with three balls to spare.
England all-rounder Chris Woakes was socked for 51 in his four overs as the Falcons side completed a quickfire double over the Bears and handed them their third successive defeat.
Hain batted beautifully but needed support and found it from Dan Mousley and, after Mousley was bowled through a lap by Zak Chappell, from Woakes, who transformed the innings with 23 from 11 balls in a dazzling stand of 48 in 18 balls with Hain.
Woakes was yorked by Zaman Khan but Hain was at his most destructive in the closing overs, thumping 36 from his last eight balls faced.
The Falcons faced a testing target but, after riding their luck early on, Reece and Haider Ali played sweetly to raise 50 from 33 balls. They set down the perfect platform before being parted in scruffy fashion when Haider Ali charged and missed at Danny Briggs. Davies missed the stumping at the first attempt but, with the batter down the track, had time to complete it second time round.
Moeen, playing his penultimate game for the Bears before he departs on Ashes duty, applied a brake with an astute spell which brought the wicket of Reece, bowled through a slog sweep. As the required rate escalated, and Wayne Madsen suffered a rare failure when he holed out to Mousley, the pressure increased on the Falcons.
Du Plooy went to the crease with that pressure at its height. He needed to hit brilliantly from his first ball - and did so to take his side to a victory which tightens the North Group table right up.