It volition spell down arsenic 1 of the biggest upsets successful FA Cup history.
Penalties either broadside of half-time from midfielder Gavan Holohan gave the Mariners a two-goal cushion and contempt Saints defender Duje Caleta-Car mounting up an agonising finale, the visitors held connected to spark chaotic celebrations among the Grimsby players, unit and 4,000 travelling supporters wrong St Mary's.
Mariners fans tin present look guardant to a travel to European hopefuls Brighton successful their archetypal quarter-finial since 1938-39, erstwhile they mislaid to beaten finalists Wolverhampton Wanderers successful the semi-finals.
Paul Hurst's Grimsby are lone the sixth squad from the 4th tier oregon beneath to scope the quarter-finals since the instauration of the Fourth Division of the Football League successful 1958-59, and lone the 2nd since 1989-90.
It is besides the archetypal clip they person beaten top-flight absorption arsenic a fourth-tier broadside successful the FA Cup since January 1989, erstwhile they defeated Middlesbrough successful the 3rd round.
'I said we could suffer 10-0'
"I'm successful shock," Hurst, whose broadside are 16th successful League Two, told BBC Radio 5 Live. "I'm truthful delighted for the owners and supporters, and the unthinkable distant support.
"I [told the players] we could suffer 10-0. I was saying I mightiness person to bring a blindfold. It's ever the fearfulness - if a Premier League squad turns up, they tin stroke immoderate League Two broadside away."
The Mariners lone returned to the EFL aft finishing sixth successful the National League past season, and needing other clip successful each 3 play-off games - edging past Notts County and Wrexham earlier overcoming Solihull Moors successful the final.
ITV summariser Ally McCoist admitted helium "didn't springiness Grimsby a chance" earlier kick-off.
"I couldn't spot a mode they would get a result," helium said. "It's magic."
"We request to speech astir Southampton different time due to the fact that they person been shocking. It's each astir Grimsby. What a nighttime for those 4,000 fans.
"It's 1 of the top nights successful their history."
'Eighteen months successful dreamland'
Speaking connected BBC Radio 5 Live, Alex Green of the DN35 Grimsby Town podcast said helium backed his squad to propulsion disconnected an upset against the Premier League strugglers aft seeing disconnected higher-ranking absorption successful each of the erstwhile rounds.
Town overcame League One trio Plymouth Argyle, Cambridge United and Burton Albion successful rounds one, 2 and 3 earlier thumping Championship broadside Luton successful a fourth-round replay past month.
"We played Luton and I preferred to play Southampton," helium said. "The show was incredible.
"We're a precise underrated knockout shot nine - truthful galore teams person recovered that out. Compare our resources to idiosyncratic similar Wrexham - they massively outstrip us. It's been 18 months successful dreamland.
Manager Hurst is present successful his 2nd spell successful complaint astatine Blundell Park, having antecedently managed them alongside Rob Scott from 2011 to 2013.
He was reappointed successful December 2020 pursuing the departure of Ian Holloway but was incapable to forestall the nine from slipping backmost into the National League for the archetypal clip successful 5 years.
"Some managers conscionable click astatine clubs, and helium does that astatine this club," Green continued.
"The occupation present is, we spell from immoderate fans disgruntled that we are 16th to being disquieted Hurst mightiness spell elsewhere.
"The emotion helium has astatine this nine is sensational."
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