The Saints' victory came after Ipswich conceded twice in stoppage time to lose at Cardiff, while leaders Leicester were held at Hull.
Recap Saturday afternoon's Championship action:
Cardiff 2-1 Ipswich
Cardiff City extended their unbeaten home H2H run to five matches – but only just, as it took two goals in injury time to defeat Ipswich Town 2-1 after Kieffer Moore had seemingly won it against his former club.
Blackburn 1-1 Plymouth
Blackburn Rovers and Plymouth Argyle remain in the midst of the hotly-contested relegation battle following a 1-1 draw at Ewood Park. The result leaves the hosts without a victory in seven Championship matches.
Hull 2-2 Leicester
Jamie Vardy hit a brace of equalisers in an entertaining 2-2 draw between Hull City and Championship leaders Leicester City at the MKM Stadium, giving the hosts their fourth successive draw in the process.
Millwall 1-0 Birmingham
Millwall struck late to steal all three points as they beat Birmingham City 1-0 at the Den, meaning the Blues have now failed to win in any of their last six away matches (D1, L5).
Norwich 5-0 Rotherham
Gabriel Sara scored two and assisted one as he helped Norwich City cruise to a 5-0 win over doomed Rotherham United and see the Canaries climb two places into the coveted Championship play-off spots.
Preston 1-2 Stoke
Against all odds, Stoke City put up a brave display against Preston North End at Deepdale to earn all three points, inflicting a first defeat on the Lilywhites in eight Championship games in the process.
QPR 0-2 Middlesbrough
Middlesbrough ended Queens Park Rangers’ four-match unbeaten run after second-half strikes from Emmanuel Latte Lath and Marcus Forss secured Boro their first win in six visits to Loftus Road.
Southampton 4-2 Sunderland
Southampton reignited their automatic promotion hopes with a dramatic 4-2 victory in the EFL Championship as Sunderland slumped to their sixth-straight defeat.
Watford 1-2 Coventry
Watford surrendered a first-half lead to fall to a 2-1 defeat at the hands of playoff-chasing Coventry City, with a Haji Wright double ensuring it is nine games at Vicarage Road without victory for the home side.
