Because national team give him 12 cr.( Current year payment and 15 cr. Untill previous year) for 2 months and ipl team was paying arround 5-7 cr. Yearly
There is a huge difference in bowling duos in both the matches - NZ had Ferguson, Boult in their death overs while MI had Bumrah, Unadkat and Dhoni has a very good record against Unadkat so it wasn't difficult for MSD to score against him
Because national team give him 12 cr.( Current year payment and 15 cr. Untill previous year) for 2 months and ipl team was paying arround 5-7 cr. Yearly