A top-four finish looked like a distant dream for the star-studded squad after they succumbed to their sixth consecutive defeat of the season against table-topper Kolkata Knight Riders last month.

Bengaluru, chasing their maiden IPL title, staged a remarkable turnaround and Saturday's 27-run victory against defending champions Chennai Super Kings in a virtual playoff shootout was their sixth victory on the trot.

Du Plessis (54) and the league's leading scorer Virat Kohli (47) gave Bengaluru a strong start and their middle order followed suit to steer the team to a commanding 218-5 in their final group match.

Chennai managed 191-7 in reply in the rain-affected match as Bengaluru joined Kolkata, Rajasthan Royals and Sunrisers Hyderabad in the playoff.

"It felt like a day-five Test match," du Plessis said explaining how difficult the pitch was to bat on after rain interrupted play.

"For me and Virat to just get through it and find a way somehow...and then in the back end to get a 200-score was unbelievable."

Middle order batters Rajat Patidar, Cameron Green, Dinesh Karthik and Glenn Maxwell produced breezy cameos to take Bengaluru past the 200-mark.

"That's been our last six games, hasn't it? Contributions from many batters with good intensity and good strike-rates," player-of-the-match du Plessis said.

"At the beginning of the season, we felt like we were a little slow and we wanted a bit more intent in our batting innings. And to have done that again is awesome."