Bengaluru defeated Lucknow by five wickets to draw level on eight points with Rajasthan Royals, edging ahead on net run-rate.
While veteran batter Virat Kohli remains the headline act and is the leading IPL run-scorer this season with 228 runs, it is the depth of the bowling unit that has underpinned Bengaluru's early consistency.
Australia quick Hazlewood struggled with hamstring and Achilles injuries last year and missed the Twenty20 World Cup, but after being eased back slowly into Bengaluru's campaign he is starting to look sharper, vice-captain Jitesh Sharma said.
"He's got rest, so he becomes quicker, fitter. He's very confident about his body now," he told reporters.
"He has worked really hard on his injury and he's like a more improved player than last year."
Hazlewood's comeback has coincided with the emergence of uncapped pacer Dar, who was signed for 60 million Indian rupees ($643,245) ahead of the 2025 season as a long-term investment.
Dar featured only twice during last year's title run, with Hazlewood, Bhuvneshwar Kumar and Yash Dayal the established pace options.
Against Lucknow, Dar rewarded that patience, combining with Hazlewood on a dry surface to deny Lucknow any early momentum and returning figures of 4-24.
Hazlewood complemented the effort with a miserly 1-20, while Krunal Pandya provided control through the middle overs.
"He (Dar) has worked a lot on yorkers and slower ones. He knew the IPL was around the corner and how one has to be perfect to play with a certain intensity," said Jitesh.
"Errors will be there, so you practice so much that it becomes muscle memory. That's what helps you perform under pressure."
Bengaluru next host Delhi Capitals on Saturday.