The New Zealand has been traded by the Delhi Capitals while Ankit Rajpoot has moved to Rajasthan Royals
Reigning Indian Premier League champions Mumbai Indians have acquired Trent Boult for the 2020 season.
The 30-year-old joins from Delhi Capitals, where he spent the last two editions of the franchise competition.
He has previously represented Sunrisers Hyderabad and Kolkata Knight Riders in the IPL and has taken 38 wickets in 33 matches.
New Zealand's left-armer took five scalps at 32.60 during this year's event as the Capitals reached Qualifier 2 before missing out on a place in the final.
Meanwhile, seamer Ankit Rajpoot has moved to Rajasthan Royals from Kings XI Punjab.
The right-armer has taken 22 wickets during his IPL career and is the only uncapped player to take a five-for in the tournament's history.
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