Buttler was the difference between the two sides as the hosts atoned for their previous Twenty20 outings to secure a 1-1 series draw with the Proteas in a rain-affected match to round off the international summer.
“Jos’s was a game-changing innings,” Broad told Sky Sports.
“We know how good he is, he’s shown on the county circuit that he does that, this is the first time he’s done it in international cricket and going into the World Cup he can be very special.”
Buttler smashed his 32 in just ten balls – three sixes and two fours – while South Africa’s Wayne Parnell suffered an over in which he was dispatched for 32 runs – the second most expensive over in Twenty20 history.
“The batting showed a bit of adaptability tonight. Jos jumped up the order because there were only four overs to go and those 10 balls changed the game,” Broad added.
The tourists won the toss and AB de Villiers inserted England in a match that was just 11 overs per side due to the Warwickshire weather.
Buttler’s county colleague, Craig Kieswetter, set thing up nicely at the top of the order with an assured 50 from just 32 balls, and after Buttler’s fireworks, the hosts had a formidable 118-5 from their 11 overs.
The Proteas were never really at the races in their run chase and only the dependable Hasim Amla (36) really troubled the England bowlers as they slumped to 90-5 from their 11 overs.
Tim Bresnan (2-14) and Graeme Swann (2-24) stalled any chance of a South Africa victory, while debutant Danny Briggs picked up his first Twenty20 wicket after Faf du Plessis mistimed a shot to Eoin Morgan at mid-off.
The victory will give England momentum going into the ICC World Twenty20 which starts later this month following a long, hard summer that has been tough both on and off the field.
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BIOGRAPHY: Ethan Hazard
BIOGRAPHY: Daniel Sturridge