Tahir took 2/23 to finish with 26 wickets, one more than Kagiso Rabada's tally.
Tahir now has 23 wickets, 2 behind Bumrah, while de Kock breached the 500-run mark.
Chennai Super Kings' 99 wins are second-most in IPL history, after Mumbai Indians' 105.
Of active batsmen, de Kock is the leading run scorers, but he is 200 runs behind Warner. Tahir, on the other hand, needs 5 wickets to win the Purple Cap.
Quinton de Kock jumped five spots, while Khaleel Ahmed entered top ten.
The two most successful IPL teams square off again, but victory in this instance is a tad more important to Mumbai.
Rajasthan Royals will host Mumbai Indians at Sawai Mansingh Stadium, Jaipur, in Match 36 of IPL 2019.
Rabada now has 19 wickets, 4 more than anyone else, while his South African teammate de Kock entered the top five.
MI will host CSK for the 15th match of IPL 2019 at Wankhede Stadium.
The 1st T20I between South Africa and Sri Lanka will be played at Newlands in Cape Town.