Signing forward Aaron Connolly from Sunderland was a "no brainer" for Millwall, says Lions head coach Alex Neil.
Republic of Ireland international Connolly's move to The Den was announced shortly after Tom Bradshaw's exit to Oxford United had been confirmed on Thursday.
Connolly, 24, joined the Black Cats from Hull City in the summer but only scored two goals in 11 appearances for the club.
Speaking ahead of Saturday's Championship fixture against the Tigers, Neil said it was "fair to say" Connolly had not played as much as he would have liked at the Stadium of Light.