Grant Leadbitter scored his second late penalty of the season to secure three points for Sunderland and a 2-1 win over former club Ipswich.
The Tractor Boys lost for the third successive away game after Leadbitter, who scored the winner against Peterborough in September, sent goalkeeper Tomas Holy the wrong way with six minutes of this Sky Bet League One contest remaining.
Jack Lankester had initially equalised for second-placed Ipswich with seven minutes remaining of the first half when his effort bounced in off the inside of the far post.
That followed Charlie Wyke's eighth minute opener at the Stadium of Light when he controlled and finished Lynden Gooch's neat pass into the area.
With the score level at the break, Sunderland did look more dangerous after the restart but they needed a helping hand with 18 minutes remaining.
Ipswich midfielder Andre Dozzell was given a straight red card for a strong challenge on Leadbitter in the centre of the pitch.
And when referee Peter Wright deemed Aristote Nsiala's attempted clearance had hit Mark McGuinness' arm with seven minutes left, Leadbitter struck the penalty that secured Sunderland three points.