Callum Brittain was sent off as ten-man Blackburn Rovers were beaten 4-0 by Southampton at St Mary's.

Goals in each half from Samuel Edozie and Stuart Armstrong ensured the Saints extended their 13-match unbeaten Championship record, inflicting a third defeat in four matches for Jon Dahl Tomasson's side.

In truth, it was a deserved victory for the hosts even before they had a man advantage. Russell Martin's side pressed aggressively as Rovers played out from the back and dominated proceedings without creating many clear-cut chances in the first half.

They got the lead just before the break though when Edozie got in front of Adam Wharton and Leopold Wahlstedt to knee the ball in from a corner. It was a soft goal to give away after a battling first-half performance.

The second half was more one-way traffic and things went from bad to worse when Brittain was dismissed. On a yellow, the defender booted the ball away in frustration and was sent off.

Southampton killed the game shortly after with Armstrong finishing off a nice team move with a close-range finish past Wahlstedt. It was no more than the hosts deserved, with Rovers unable to solve the tactical conundrum that Saints posed.

It could've been worse had Carlos Alcaraz's 'panenka' not gone over the bar from the penalty spot after Hayden Carter brought down Sekou Mara in the box.

Mara did get himself on the score sheet in stoppage time though as he turned in Ryan Fraser's back-post cross to compound a miserable afternoon for Rovers. 

That wasn't the end though as with virtually the last kick of the game, Alcaraz scored. He turned in the rebound after Will Smallbone's shot had been saved by Wahlstedt.

Tomasson's side came into the game looking to build on Tuesday's 2-1 win over Bristol City. The head coach made one alteration, bringing James Hill back into the team for Niall Ennis.

It meant Rovers went into the game, not for the first time this season, with no recognised striker. Sam Szmodics was the furthest man forward, with Andrew Moran in support when Rovers had the ball.

In a tactically fluent game, Saints also played a curveball with Adam Armstrong starting on the right wing. It created a condensed, saturated midfield area, with both teams pressing high and neither using an auxiliary striker.

Southampton started on the front foot but Rovers weathered the storm and began to find their way into the game. The best chance came when Wharton was brought down on the edge of the box, Szmodics' free-kick was fumbled and Callum Brittain couldn't force the rebound in.

Wahlstedt gave Rovers fans a heart-in-mouth moment as he was almost tackled on his goal-line by their former striker, causing the goalkeeper to get treatment. He soldiered on with Joe Hilton waiting in the wings for a potential league debut.

The Rovers goalkeeper was in the stick of the action shortly after as he got down to keep out Will Smallbone inside the box. All of the danger was coming down Southampton's left, with Edozie proving a particulary handful.

The former Manchester City winger would prove to be the first goal-scorer, though not how you'd have expected. James Bree's low corner somehow reached the six-yard box and he kneed it in from close range.

A.Wharton was marking Edozie in front of Wahlstedt but neither the midfielder nor the goalkeeper did enough to prevent the Southampton man scoring. It was a very soft goal to give away right before the break.

The Rovers goalkeeper went someway to redeeming himself as he kept the score at one shortly after half-time, flinging himself to the left to deny Armstrong's curling effort.

Their task was made all the harder when they were reduced to ten men before the hour mark. Brittain, already on a booking, was shown a second yellow card for kicking the ball away.

It was a moment of foolishness from the defender, who looked disappointed in himself the moment it happened. However, the inconsistencies in the application of these new rules are jarring. Joel Aribo made the same offence in the first half, albeit less obviously, and didn't receive a caution.

Southampton were in full control, a goal and a man up on their opponents. Rovers tried to stop the bleeding in a 4-4-1 shape but Edozie continued to pull the string.

Rovers' best hope was a counter-attack and a lovely ball from Hill found substitute Harry Leonard but his shot was down the throat of Bazunu.

It proved to matter little because the game was over as a contest by the 65th minute. Flynn Downes latched on to Will Smallbone's through ball, cut inside and left it for Armstrong to finish into the bottom corner.

Whether it was with 11 or ten men, the hosts were a class above Rovers. it's not much of a surprise given the gulf in resources and Premier League quality littered within their squad.

Like against Ipswich Town, Leicester City and Leeds United more recently, this was a stretch too far for this young, depleted squad. They were on the back foot from the first minute.

The final 25 minutes were more like a testimonial, with Southampton toying possession. Blackburn sat in, conserving energy and not risking getting beaten up on the counter-attack, a man light and two goals down.

Wahlstedt made another impressive stop to deny Joel Aribo but it was just a temporary reprieve. Mara was brought down in the box by Carter but fellow substitute Alcaraz chipped the ball over the bar, letting Rovers off the hook.

The Saints did a third in stoppage time though as Mara escaped Scott Wharton and tapped in Fraser's back-post cross.

Unfortunately, there was more pain to come as Alcaraz made it four moments later. Rovers didn't shut down Smallbone on the edge of the box and his shot was saved by Wahlstedt but the Saints attacker was first to react.

This was again a reminder of the gulf in class between the top four and the chasing pack. The defeat drops Rovers into 11th, four points adrift of the play-off places.