After last week's first-leg goalless draw at The Riverside Stadium, Southampton and Middlesbrough will complete their controversial battle for a Championship playoff final spot when they meet in their semi-final second leg on Tuesday.
The hosts sealed home advantage for the decisive second leg at St Mary's by finishing above their opponents in the Championship table on goal difference, with the tie set to be remembered for the antics dubbed 'Spygate 2.0'.
Match preview
Southampton head back to St Mary's on Tuesday aiming to move within one game of making an immediate return to the Premier League.
They took a playoff spot by earning 68 points from 33 matches under Tonda Eckert, who arrived in November, to finish on 80 overall after a slow start.
That was largely down to an eye-catching run to end the campaign and crash the promotion fight, having gone 19 games unbeaten including 14 wins, culminating in a final-day 3-1 away victory over Preston North End to take fourth spot thanks to goals from Taylor Harwood-Bellis, Ross Stewart and Cyle Larin.
Then heading into the playoffs as the form team, the Saints travelled north for the first leg on Saturday amid off-field noise around a member of staff spying on a Middlesbrough training session, and while awaiting confirmation of any punishment for the misconduct, they were able to come away on level terms after a goalless stalemate.
Now heading into the decisive second leg with home advantage on their side, Southampton will bid to come out on top and extend their long Championship unbeaten streak with a win to book a second trip to Wembley in a matter of weeks after their FA Cup semi-final close call against Manchester City.
Their visitors, meanwhile, make the long trip south aiming to make it four Championship games unbeaten against Southampton this term including two wins to move closer to a Premier League return for the first time since 2016-17.
Middlesbrough found themselves in the automatic promotion fight for the vast majority of the Championship season but would eventually finish fifth on 80 points from their 46 games, four short of the top two.
They were cost by a seven-game winless run between mid-March and mid-April, including three defeats, before Kim Hellberg's side were at least able to end the regular season with a pair of wins and an away draw against Wrexham.
Then turning their focus to a playoff semi-final all but overshadowed by the off-field 'spygate 2.0' antics of their opponents, Middlesbrough failed to make their domination count last weekend on home turf, instead settling for a goalless draw leaving everything in the balance ahead of the St Mary's trip.
Hellberg's men now know that if they are to punch their ticket to Wembley, they must prevail away from home to settle the tie.
Southampton Championship form:
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Southampton form (all competitions):
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Middlesbrough Championship form:
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Team News
Southampton remain unable to call on defenders Jack Stephens and Mads Roerslev on Tuesday due to ongoing injuries.
They should field a similar starting XI to Saturday's first leg, with Nathan Wood and Taylor Harwood-Bellis bound to continue in the middle of a back four, although Shea Charles will hope to displace Flynn Downes or Caspar Jander and start in midfield.
Cyle Larin will hope to again lead the line, having netted eight league goals since his January arrival, but he faces competition from Ross Stewart, while Leo Scienza, former Middlesbrough man Finn Azaz and Tom Fellows should continue behind the preferred front man.
Middlesbrough are still without centre-backs Alfie Jones and Darragh Lenihan alongside Alex Bangura, while star midfielder Hayden Hackney also remains sidelined and is unlikely to return from the issue that has ruled him out since mid-March.
In his absence, Riley McGree joined mainstay Aidan Morris in midfield on Saturday, but Alan Browne may be brought in to strengthen their central unit.
Ahead of them, David Strelec, Morgan Whittaker and Tommy Conway will all hope to keep their spots in attack, having netted eight, 13 and 14 league goals respectively this term.
Southampton possible starting lineup:
Peretz; Bree, Harwood-Bellis, Wood, Manning; Charles, Jelert; Fellows, Azaz, Scienza; Stewart
Middlesbrough possible starting lineup:
Brynn; Ayling, Fry, Malanda; Brittain, Morris, Browne, Targett; Whittaker, Conway, McGree
We say: Southampton 2-1 Middlesbrough (Southampton win 2-1 on aggregate)
Like Saturday's first leg, we can only envisage Tuesday's game being a tight and hard-fought affair and give a slight edge to Southampton with home advantage.
Given their formidable run in the second half of the campaign, the quality throughout their squad and the loss of Hackney for the visitors, Eckert's side should back themselves to get over the line and book their Wembley ticket.
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