12:59 PM ET
The Brazilian midfielder was sent off for a high challenge on Carlos Alcaraz following a VAR review. Referee Anthony Taylor initially showed Casemiro a yellow card, but it was upgraded after Taylor looked at the incident on the pitchside monitor.
Both David De Gea and Gavin Bazunu made good saves to keep the game goalless and it's likely to be United who feel happier with the result.
1. Man United hold on, Southampton miss out
Under manager Erik ten Hag, United have produced some exciting attacking football, but Sunday was all about grit and determination. Playing with 10 men from the 35th minute after Casemiro was shown a straight red card for a reckless challenge on Alcaraz, United dug in to make sure they extended their unbeaten run at Old Trafford to 22 games.
Ten Hag needed De Gea to make two good save, but Southampton goalkeeper Bazunu was also impressive, making sharp stops to deny Raphael Varane and Bruno Fernandes. In the end, Southampton, bottom of the Premier League table, will feel like it's a missed opportunity having played with a man advantage for so long, while United will be happy to collect a point from a game they could have quite easily lost.
The bigger disappointment for Ten Hag will be losing Casemiro for the next four domestic games -- including the trip to Newcastle on April 2 -- while a late injury to Alejandro Garnacho is also something he could do without.
Casemiro was never shown a straight red card during his time at Real Madrid, but he's been shown two in his last three Premier League appearances.
2. Ten Hag has a conundrum with De Gea
Ten Hag has seen the best and worst of De Gea in the space of four days this week, and it highlights the problem for the United boss as he decides what's next for the goalkeeper.
On Thursday against Real Betis, De Gea's kicking was poor and it put his teammates in trouble more than once. One misplaced pass almost allowed the Spanish side to take the lead late in the first half before United took control of the tie.
Against Southampton, though, De Gea showed that he is still one of the best shot-stoppers in the world with a reflex save to prevent Theo Walcott scoring with a header from six yards out. It was the kind of save he has produced again and again over the last decade at Old Trafford.
You can understand why Ten Hag might want a goalkeeper who is better with the ball at his feet -- particularly when you're looking to build out from the back -- but the risk is that any new addition isn't as good at making saves. It's a question for Ten Hag to solve when he implements the second stage of his rebuild in the summer.
3. Bazunu has his best game for Southampton
There have been questions asked about Bazunu this season after Southampton spent close to £16 million in the summer to bring in a goalkeeper who a year ago was playing in League One. On loan at Portsmouth from Manchester City last season, it's looked at times this season that the third tier is the 21-year-old's level but at Old Trafford he looked right at home in the Premier League.
With Southampton playing against 10 men for nearly an hour, Bazunu didn't have the busy afternoon he was probably expecting, but he still pulled off two wonderful saves to make sure United didn't snatch all three points.
In the first half, the Republic of Ireland international raced across to the back post to deny Raphael Varane by throwing himself at the Frenchman. Then, after half-time, he produced a fantastic stop to push Bruno Fernandes' effort onto the inside of the post. He was also quick off his line more than once to get the better of duels with Marcus Rashford.
Bazunu still has work to do to win over the majority of Southampton fans, but a clean sheet at Old Trafford is a good place to start.
Best and worst performers
- Gavin Bazunu, GK, Southampton: The 21-year-old made two outstanding saves from Varane and Fernandes.
- David De Gea, GK, Man United: Expertly pushed Theo Walcott's header over the bar from six yards out.
- Theo Walcott, MF, Southampton: The forward had, and squandered, his chances to win the game for Southampton.
- Casemiro, MF, Man United: His challenge on Carlos Alcaraz was high and he can have few complaints about the VAR review.
- Wout Weghorst, ST, Man United: Spent most of the first half arguing with the referee and was sacrificed early after Casemiro's red card.
Highlights and notable moments
Did this seem like the right call for Casemiro? Really does seem so.
Southampton midfielder James Ward-Prowse is known for his set-piece heroics, and he came so close to breaking the stalemate with an excellent free-kick.
Was a red card the correct call for this tackle by Casemiro? 🤔 pic.twitter.com/ZWi3qhc2kI— ESPN FC (@ESPNFC) March 12, 2023
In the end, United kept trying... but a point feels like the fair share given how much the game changed with Casemiro's first-half red card.
After the match: What the players/managers said
"A few months ago we would have lost this game. Hopefully this can give us some momentum to keep building from. You see from today's performance that we can perform against any team in this league and we just need to continue." -- Southampton goalkeeper Gavin Bazunu, to Sky Sports
"I think Casemiro was unlucky. He tried to touch the ball and his foot came up high. I think the referees need to show more consistency. Sometimnes they show a red card and sometimes they don't. It's going to be tough, he's a big player. We will miss him for four games but we have a big squad. We have players coming from the bench who do well. We will keep working hard." -- Manchester United goalkeeper David de Gea, to Sky Sports, regarding Casemiro's red card
Key stats (provided by ESPN Stats & Information research)
- Casemiro: Second red card with Man United (first since Feb. 4 in the Premier League). In 37 competitive matches with Man United across all competitions, he equals his total amount of red cards in his entire Real Madrid career. This equals his total amount of red cards (336 games).
- Manchester United fails to score in consecutive Premier League games for the first time since the final two games of the 2021-22 season (4-0 loss to Brighton, 1-0 loss to Palace)
- Via Opta: Casemiro is the first player to receive two red cards in a single Premier League season for Manchester United since Nemanja Vidic in 2013-14.
Manchester United: Ten Hag's side have a potentially fun week ahead, with a Europa League last-16 second leg date with Betis on Thursday -- and with a 4-1 aggregate lead -- setting up Sunday's FA Cup quarterfinal clash with Fulham.
Southampton: It's nothing but Premier League action from here on out for the struggling Saints, who have a midweek game with Brentford (March 15) followed by Tottenham's visit on Saturday.