January arrival number five ... Conor Coventry joins Rotherham United on loan from West Ham United
The arrival of the West Ham United youngster comes 24 hour after striker Jordan Hugill joined the Millers on a three-and-a-half-year contract.
He played well in the Dons' 2-1 win at AESSEAL New York Stadium in March when both clubs were going for promotion.
He becomes the fifth signing of a busy transfer window in which the Millers have strengthened significantly as they look to consolidate their place in the second tier.
Coventry, an attack-minded player who is good on the ball, is rated highly by West Ham who have used him in their Europa Conference League campaign this season.
Rotherham have twice made attempts to bring him to New York in the past.