After a goalless first half, Lions defender Jake Cooper opened the scoring just before the hour mark after a corner.
The Black Cats then managed to equalise nine minutes from time when Alex Pritchard’s free-kick was converted by Dennis Cirkin.
Mowbray’s side will now prepare for next week’s FA Cup replay against Fulham.
Here’s how Phil Smith rated the Sunderland players against Millwall:
Mowbray’s side will now prepare for next week’s FA Cup replay against Fulham.
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