Manchester United's Champions League qualification hopes suffered a blow after an equaliser deep in stoppage time from Michael Obafemi earned Southampton a 2-2 draw in the Premier League at Old Trafford on Monday.
United were poised to move up to third after Anthony Martial's 23rd minute strike had put them 2-1 ahead. But Obafemi struck late in the 96th minute to give the Saints a vital draw.
On the day when second-placed Manchester City's two-year ban from European football was overturned on appeal, meaning the top four will qualify for the Champions League as usual, United stay in fifth place on 59 points.
"It was the worst time to concede a goal but it happens in football. We have won so many games in that way. It is all part of the learning for this team. You think you have three points in the bag but we probably didn't deserve three points today," United coach Ole Gunnar Solskjaer told Sky Sports after the match.
"Southampton are a good team, they run, and run and chase. We never got into our rhythm today. We played some fantastic football at times. The two goals we scored were very, very good."
Solskjaer, who had kept the same starting XI for the fifth straight game, did not blame fatigue for the lapse in play.
"I don't think tiredness the case. It was just one of those days we did not take our chances and they took theirs. David de Gea had one really good save but apart from that we had the bigger chances but you are not going to be given three points and Southampton are a very good side," Solskjaer added.
United captain Harry Maguire called the result disappointing.
"We got ourselves in a great position to win the game but then invited pressure on ourselves by not being very good on the ball," Maguire said. "We knew we would have to grind the results out sometimes.
"When you are down to 10 men the one thing you can do is defend set plays, get your head in it and get the ball out of the box but we didn't do that. We can't be doing that if we want to get to where we want to get to."
Southampton took a shock lead in the 12th minute when Paul Pogba was robbed by Danny Ings just outside the area and Nathan Redmond's cross found Stuart Armstrong at the back post where the Scottish midfielder slotted home.
Pogba played the ball in to Martial who held off two Saints defenders before poking the ball to Rashford who made no mistake with a left-foot finish in the 20th minute.
Three minutes later United had the lead, Bruno Fernandes fed Martial on the left and the French international cut inside and smashed the ball home.
United finished the game with 10 men after Brandon Williams went off injured, with Solskjaer having no substitute opportunities, and they failed to hold on to the three points when Obafemi turned in a corner at the back post.
"Amazing. We got the draw. I am just happy I could get the equaliser," Obafemi said after the match. "It is amazing for me on a personal level but as a team we go anywhere to get three points, we got the one but it was a positive step."
Reuters contributed to this report.