MK Dons will have to come from behind at St Mary's next month if they are to reach the Johnstone's Paint Trophy Final, after Southampton took a slender advantage at stadiummk.

Michail Antonio's first-half goal settled a scrappy first leg in front of the Sky cameras and left Alan Pardew's Saints needing only to avoid defeat in the return to book a place at Wembley.

Despite being overpowered by a physical Saints side in the first period, the Dons imposed themselves after the break - putting the visitors under sustained periods of pressure as they began to find their own rhythm.

And Southampton were positively hanging on come the end of the game following Morgan Schneiderlin's dismissal, after the Frenchman raised his hands to Dons midfielder Stephen Gleeson.

But the defeat does leave Paul Ince's side in need of a huge away performance on the south coast in three weeks time - where the Dons will have to withstand a physical Saints approach that has now twice got the better of them.

Michail Antonio celebrates his goal with Morgan Schneiderlin.

Having had their noses bloodied by Southampton's smash-mouth style at St Mary's back in October, the Dons knew what was coming from Pardew's men, but seemed powerless to stop it for much of the opening period.

Given no time to settle into the passing game that saw them romp past Hartlepool at the weekend, Ince's men found themselves drawn into a direct, battling style that suited Saints down to the ground.

Utilising the physical presence of Rickie Lambert in attack, the visitors, backed by a fantastic following of around 3,000, were asking the early questions and defender Jose Fonte was almost the first to benefit - sweeping just wide from the first of many Lambert knock-downs.

Jason Puncheon, so often the catalyst for Dons attacks, looked the home side's most likely source of creativity and after Fonte had pulled down Aaron Wilbraham on the edge of the box, it was his free-kick that bent just wide of Kelvin Davis' goal on 16 minutes.

Mark Randall holds off Adam Lallana.

Southampton came again - Lambert flicking on for Schneiderlin, whose cross from the right was seized on by Adam Lallana. A slip from Danny Woodards gave the Southampton wide-man the freedom of the penalty area, but Willy Gueret stood tall to save his scuffed shot.

As balls continued to rain into the Dons box though, you sensed the breakthrough was coming and it was no surprise that Lambert was again at the heart of it.

Antonio obviously saw it coming as Lambert headed down a Joseph Mills free-kick - the on-loan Reading winger improvising brilliantly to hook a bouncing ball in off the post from 15 yards.

Dons' hopes took a further knock nine minutes before half-time when midfielder Peter Leven was forced off with a groin problem. But his replacement, on-loan Arsenal man Mark Randall, was not about to pass up the opportunity to make an impression.

Aaron Wilbraham hit the post for the Dons late-on.

Classy in possession and aware of everything going on around him, Randall's demeanour screams Arsenal, but it was his bite in the tackle that truly introduced him to proceedings. His crunching challenge on Schneiderlin just before half-time led to a 20-man scuffle, but suddenly Saints knew they could not longer bully the home side physically.

Having been dictated to in the first period, the Dons started calling the shots after the interval - Puncheon signalling their intent with a dynamic break out of defence that nearly put Chadwick in the clear.

And a few minutes later, Jermaine Easter had Davis scuttling across his goal to keep out a well-struck shot after turning away from his man 30 yards out.

Antonio was denied by an excellent block from Mathias Doumbe, but the Dons' influence was growing - Randall and Puncheon seeing a lot of the ball without being able to really trouble their well-drilled opposition.

Wayne Thomas clears away from Luke Chadwick.

Schneiderlin's dismissal made their jobs even harder towards the end, with Dons players prowling the final third in search of a gap to influence the game.

But it was Jude Stirling, on as a replacement for Luke Chadwick, who typically cranked up the pressure with a series of long throws Southampton struggled to properly deal with.

Hurried into badly-timed clearances and retreating desperately towards their own goal, Saints invited the Dons onto them and Davis had to be sharp to another low drive from Puncheon.

Dean Lewington battles with Michail Antonio.

And they came even closer a few moments later when a peach of a cross from Stirling from the left was diverted against the inside of the post by Wilbraham.

MK Dons (4-5-1): Gueret; Woodards, Doumbe, McCracken, Lewington (c); Easter (Baldock 74), Puncheon, Gleeson, Leven (Randall 36), Chadwick (Stirling 63); Wilbraham.

Subs not used: Carrington, Darren Powell.

Booked: Randall, Gleeson

Southampton (4-5-1): Davis; Thomas, Fonte (c), Perry, Mills; Antonio (N'Diaye 90), Wotton, James, Schneiderlin, Lallana (Holmes 72); Lambert.

Subs not used: Bialkowski, Martin, Saganowski.

Goals: Antonio 26

Booked: Davis, Thomas, James, Holmes

Sent off: Schneiderlin 79

Attendance: 7,918

Referee: Jon Moss (Yorkshire)