Looking at Mathews bowling in this WC
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No way it took two seamers to replace him. Can almost say Perera came in for him 1:1 and didn't do too badly with the bat...
The other changes were very voluntary, to go with less spinners and to change the mix of spinners involved. Unless of course someone says they'd have played with Mathews, two seamers and three spinners (in which case he case he did not do much with the bat either to go down that path)