Both clubs have fallen some way short of expectations in the Premier League so far this season, with Sunderland languishing at the foot of the table and United 11 points behind leaders Arsenal in seventh.
United were also dumped out of the FA Cup on Sunday as Swansea City claimed a shock 2-1 win at Old Trafford to pile further pressure on David Moyes.
Sunderland have already sprung one major surprise in this season's League Cup, knocking out Chelsea at the last-eight stage courtesy of Ki Sung-Yueng's extra-time winner.
In contrast to United, Poyet's men also tasted success in the FA Cup at the weekend, beating League One side Carlisle United 3-1 to reach the fourth round.
Although Sunderland will have significant concerns over their own Premier League position, it is United who will surely go into Tuesday’s match under the greatest pressure.
Sunderland's only final appearance came in 1985, when an own goal from Gordon Chisholm enabled Norwich City to claim a 1-0 victory at Wembley.
Fabio's dismissal came just four minutes after he had been introduced as a replacement for Rio Ferdinand, who appeared to suffer a knee injury.
Sunderland are without goalkeeper Keiren Westwood (shoulder) and defender Carlos Cuellar (thigh), while captain John O'Shea, who spent more than 10 years with United, has been troubled by a persistent shoulder problem in recent weeks.
