The England wicketkeeper-batsman’s unbeaten 94 off 53 balls against the Mumbai Indians kept his Rajasthan Royals in the IPL playoff race and matched Sehwag’s mark set in 2012.
Butler hit nine fours and five sixes as the Royals romped home by seven wickets.
“I’m really enjoying it, found some good form, it’s a do-or-die situation and I’m full of confidence so want to keep it going,” said Buttler, who cost the Royals US$653,840 (RM2,584,303).
“I’m in a good head-space and looking forward to the next game,” he added after Sunday’s win.
Buttler, 27, will get the chance to break the record against Kolkata Knight Riders on Tuesday with his 94 coming just days after notching his highest Twenty20 score of 95 not out against Chennai Super Kings last week.
That followed knocks of 67 off 26 balls, 51 (off 39), and 82 (off 58) and means Buttler has amassed 509 runs in 12 games in 2018 at an average of 56.55 and a strike-rate of 153.77.
“He has been in great form. He didn’t give us any chances,” conceded Mumbai skipper Rohit Sharma.
The Royals’ win also ensured a final-four place for the Mahendra Singh Dhoni-led Super Kings, who stand behind table-toppers Sunrisers Hyderabad in the eight-team table.
The Royals lies fifth with two matches remaining with the top four moving into the playoffs.
This year’s seven-week tournament has US$8 million (RM31.6 million) in prize money, including US$4 million (RM15.8 million) for the team crowned champions at the May 27 final in Mumbai.