Nottinghamshire 198 for 6 (Clarke 57) beat Derbyshire 185 for 6 (Madsen 68) by 13 runs
Nottinghamshire moved four points clear at the top of the North Group when they beat Derbyshire by 13 runs in the T20 Blast at Trent Bridge.
Wayne Madsen led a spirited chase with 68 from 46 balls while Matt Critchley hit 44 from 28 but Jake Ball bowled well under pressure to take 2 for 36 as the Falcons closed on 185 for 6 and are still without a win.
It was no surprise when the Outlaws elected to bat first and although they lost Chris Nash in the second over when he chipped to deep midwicket to give Dustin Melton his first T20 wicket, Hales and Clarke laid the platform for another imposing total.
Hales hit four consecutive fours off Michael Cohen as the Outlaws took 65 from the Powerplay before Clarke pulled and drove Alex Hughes for the first sixes of the innings.
The pair added 93 in 8 overs before Hales skied Hughes to long on and although Clarke was dropped on 50 by Critchley running in from long-off, he pulled Hughes to long-on in the next over.
Despite that lapse, the Falcons had managed to keep their discipline in the field but the Outlaws moved into overdrive as 45 came from the last four overs.
Dan Christian smashed Madsen for successive sixes before he failed to clear long off but Tom Moores pulled the fifth ball of the over for another maximum. Moores was bowled aiming a big pull at Melton who conceded only three from the 18th over but Ben Duckett took consecutive boundaries off Cohen before Steven Mullaney dispatched the penultimate ball of the innings for six.
The Falcons lost Luis Reece first ball, bowled by Imad Wasim, and Billy Godleman was lbw sweeping Matthew Carter but Madsen and Leus du Plooy lifted them to 56 for 2 at the end of the Powerplay.
Mullaney had du Plooy caught at mid-off but with Madsen astutely finding the gaps, the Falcons were still in the chase on 92 for 3 at the halfway point. Critchley swung Imad for six over midwicket and cut Ball for two fours but the seamer responded by yorking Madsen with the last ball of the 14th over.
The Falcons needed a big over and Hughes delivered in the 16th, pulling Samit Patel for six and sweeping him for two fours. Ball returned to have Critchley lbw and bowled a superb penultimate over which cost only five leaving the Falcons needing 23 off the last over which proved beyond them.