Jack Haynes struck fifty on debut but Notts Outlaws were handed a defeat by Northamptonshire Steelbacks who won their second game in as many days in the Vitality Blast.
The visitors were led by David Willey who hits 79 off 34 balls to chase 154 inside 14 overs with eight wickets in hand.
His contribution followed commendable bowling performances from Saif Zaib and George Scrimshaw, each of whom took three wickets to peg the Outlaws back from a bright start at Trent Bridge.
Outlaws quickly found themselves on the front foot after losing the toss - despite Alex Hales top edging Raphael Weatherall to Lewis McManus in the second over - as skipper Clarke and Haynes combined.
The latter whipped his first ball in green and gold off his hips for four, setting the tone as their partnership reached 50 within the powerplay.
By the halfway point, that partnership had nearly doubled with the Outlaws 104-1, only for Clarke to hole out to deep extra cover two short of his own half-century, breaking a stand of 95.
Haynes anchored the innings, reaching his fifty after Will Young was run out taking an optimistic single, before Tom Moores miscued to long on for nine.
Haynes was ultimately dismissed for 51 after being caught by Sikandar at deep mid-wicket in the 14th over, with the Outlaws at 130-5, the first of six wickets to fall for 25 runs.
Matt Montgomery was bowled attempting to sweep Raza for 11, before Harrison’s stumps were uprooted by Willey.
Scrimshaw then forced Lyndon James to sky to mid on, trapped Dillon Pennington lbw and induced an edge from Olly Stone.
In reply, Northants’ Vasconcelos misjudged a ramp shot and chipped the ball to Clarke in the early knockings before debutant Ben Lister narrowly missed Willey’s edge in his opening over.
South African Matthew Breetzke found his rhythm, though, and hit three boundaries in three balls to kickstart his side’s charge.
Willey emerged as the standout performer by striking four sixes in a row off Calvin Harrison before being caught for 79 off 34 balls, with James taking the catch on the boundary.
He had, though, catapulted Steelbacks into a position of dominance with 35 required from the final 10 overs.
As it was, it took them only another 20 balls to get the job done, Breetzke and Ravi Bopara picking up two more maximums each before the former lofted Montgomery’s off-spin through long off for the winning boundary, completing his half-century in the process.