United led at the break, courtesy of Jadon Sancho's first home goal in the Premier League, with the winger tapping home an unselfish pass by his fellow England international Marcus Rashford.
However, the Saints responded soon after half-time when Che Adams was allowed to drift in from the left and fire in a finish off the far-hand post.
Harry Maguire almost came up trumps with a late winner but his header was brilliantly saved by Fraser Forster during a fractious ending to the game.
There were some bright individual performances despite the disappointing nature of the result, which is a blow to our hopes of reaching the top four.