The off-spinner took three wickets in a single over twice on his way to the staggering figures to surpass Arul Suppiah's 6-5 for Somerset against Glamorgan at Cardiff in 2011
Leicestershire v Birmingham report
Foxes hero Colin Ackermann struggled to comprehend what he had done after taking a world record 7-18 as his side defeated the Birmingham Bears by 55 runs.
More than 30 bowlers in world cricket have taken six wickets in an innings but Ackermann became the first to take seven.
The off-spinner took three wickets in a single over twice on his way to the staggering figures to surpass Arul Suppiah's 6-5 for Somerset against Glamorgan at Cardiff in 2011.
"It has not really sunk in, it is quite an extraordinary thing," he said. "To take seven wickets is incredible.
"Never in a million years would I have believed I would have the best T20 figures ever.
"It is the first time it has really turned at Grace Road this year and I tried to use my height to get a bit of extra bounce.
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"If you can turn the ball it is a major weapon in T20 as a spinner. Even if it is only a little it is a weapon.
"I tried to get the batters to hit into the biggest part of the field into the wind and just mix my pace up a little.
"It is a great win for us. I thought Harry Swindells played beautifully at the top to set the game up for us and he and Lewis Hill deserve a lot of credit."
Bears captain Jeetan Patel was quick to take his hat off to his fellow offspinner.
"It was a fantastic performance," Patel said. "The little bit of spin that he could get and from the height that he has it become very hard for the batters.
Jeetan Patel commended his fellow offspinner
"But you can’t take away from what a great spell of bowling it was or the performance from Leicestershire.
"He hit a better length for longer than me and asked the ball to do stuff, whereas my own bowling was a little bit too full and a bit predictable.
"It was my spell that probably put them in the ascendancy!"
Courtesy of the ECB Reporters Network
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