Notts had already been defeated by Worcestershire Rapids and suffered a wash-out in their other match but had the better of their Trent Bridge encounter with Northants Steelbacks, eventually triumphing by seven wickets with 11 balls to spare.
Clarke, who has had a lean season with the bat, scored 45 from only 34 balls and put on 79 for the first wicket with Alex Hales as Notts chased down a victory target of 153 to maintain a lengthy winning streak against the Steelbacks.
“I enjoyed that. It has been a tough couple of months and it’s just nice to contribute to a win,” smiled Clarke.
He scored 50 in a second team match friendly in the week and said: “I didn’t want to turn down the opportunity of playing in a friendly in the week and scored some runs.
“It’s important to spend time in the middle and I’ve done that and faced some balls and got my rhythm back. I came off tonight and hopefully there is more in the tank.”
On his run of recent low scores, he added: “That’s the sport . It takes just one ball.
“Other years it has gone my way but this year it hasn’t.
“I’m trying to remain positive and hope scores are around the corner and hopefully over the next couple of months I can make some vital runs for the team.
“I’ve not changed anything in terms of my cricket. It’s the off-field things that have affected my form. I’ve been hitting them well in the nets but maybe I’ve lost a little bit of confidence.”
Hales followed up his 52 against the Rapids with a stylish 33.
Notts had the run chase in control right from the start, although Pakistan international Fahim Ashraf did begin with a maiden to Clarke.
Hales helped both Nathan Buck and Dwaine Pretorius over the ropes in the initial overs and Clarke then heaved Ashraf over wide long-on to end the powerplay overs on 60 without loss.
A crowd of 13,691 – a Trent Bridge record for a midweek T20 match – lapped it up as the home side found the boundary repeatedly.
Clarke was eventually dismissed by Nathan Buck and Hales followed, falling to former team-mate Graeme White but the onslaught continued.
Ben Duckett, playing against his former side, scored 26, effectively setting the contest with two sixes off Dwaine Pretorius in the 15th over.
Dan Christian, the Outlaws’ captain, enjoyed a fine match and finished with an unbeaten 22, with Tom Moores bludgeoning the ball over the ropes for the winning runs.
Earlier, the Steelbacks made 152 for eight after winning the toss and opting to bat. They limped their way to 39 for two from the opening six overs, with Matt Carter removing the dangerous Adam Rossington with the sixth ball of the match.
Josh Cobb hit both Carter and Samit Patel for sixes but was then completely bamboozled by Harry Gurney’s slower delivery and could only balloon the ball up to cover.
Christian couldn’t have had a better start with the ball, bowling Rob Keogh with his first delivery and having Matt Coles caught behind with his fifth.
The Steelbacks’ new overseas pairing of Pretorius and Fahim Ashraf mounted a counter-attack, adding 36 in just three overs together but neither could see out the innings. Ashraf was unlucky, having plundered 24 from only 14 balls he was caught by a diving Gurney at short third man, giving Christina his third wicket.
Pretorius fell to Jake Ball for 34, leaving White to muscle some useful runs in the closing couple of overs, hitting two sixes in his unbeaten 24.
On a decent surface, with a fast outfield, the eventual total appeared light and so it proved, extending Northants’ unwanted record of never having beaten Notts in the group stages.
Northants first team coach David Ripley said: “We under-clubbed on our runs.
“It was a decent pitch with a shortish boundary on one side and the start they had in the powerplay they managed their way to victory.
“Graeme (White) bowled well in that middle period and we scrapped our way back in, but we needed something special and they eased their way over the line. I think we needed another 25 runs – 175 would have been a good game.”
THE TURNING POINT - Josh Cobb had raced to 36 from 28 balls before being out-Foxed by a slower ball from his former Leicestershire team-mate Harry Gurney.
SHOT OF THE MATCH - It has been a tough summer with the bat for Joe Clarke but he will have enjoyed the mighty pulled six that deposited Nathan Buck into the back row of the stand.
UNSUNG HERO - Graeme White has always been a fine T20 bowler and he sent down his four testing overs for only 19 runs, picking up the wicket of Hales as a bonus.
WHAT’S NEXT - Local rivalry will be at stake in the forthcoming days, as Notts Outlaws play their two East Midlands rivals next. On Friday evening they travel along the A52 for an encounter with Derbyshire Falcons, followed by a home match against Leicestershire Foxes on Saturday afternoon. Northants Steelbacks have home fixtures against Birmingham Bears and Yorkshire Vikings to look forward to, on Friday and Sunday respectively.