Anderson, who was earlier said to be out of the IPL with a fractured left-hand finger, had returned home to have the injury assessed by the doctors before reaching here last night, according to the team's spokesperson.
"He went back to New Zealand to undergo treatment for the injured finger. He returned to Mumbai last night and his fitness will now be assessed. His name had never been pulled out of the squad," the spokesperson explained at the surprise development.
He was replaced in the playing eleven successfully by his compatriot Mitchell McClenaghan, who also bats left handed and bowls with the same arm.
Today, Anderson was seen bowling at his normal pace in the nets.
Anderson had scored a blistering 95 off just 44 balls last season to help MI make the play-off after a poor start during which they lost six games in a row.
This season too MI have resurrected their campaign after losing four games in a row and later a fifth. Currently they are in seventh position, just above bottom-placed Kings XI Punjab, with four wins and eight points to their credit.