Ralph Hasenhuttl says Southampton will be relegated if performances don't improve after describing Saturday's loss to Cardiff as a "disaster".
The Saints slipped back into the bottom three after the Bluebirds came away from St Mary's with a 2-1 win.
Hasenhuttl's men are now 5/1 to drop out of the Premier League, while Cardiff are 4/5 having recorded back-to-back wins in the top-flight for the first time since the 1960s.
It was a stoppage-time winner from Kenneth Zohore that saw the Welsh snatch all three points on the south coast, Southampton having got back on level terms through a 91st minute equaliser from Jack Stephens after Sol Bamba's opener for the visitors.
Having seen a win slip through their grasp the previous week against Burnley following another injury-time goal, Hasenhuttl was left frustrated by his team's failure to see out a game for the second week running.
The Austrian spoke candidly after the full-time whistle, claiming Southampton needed to buck up their ideas if they want to stay in the Premier League.
He said: “I’m so disappointed, I have problems to find the right words. It was a difficult game, as we expected it would be.
“The opponent shot three times on our goal and we conceded two goals. If we [keep doing this] we have no chance to stay in the Premier League, that is for sure.
“Giving points away in that way, it would be very, very difficult. You can talk about tactics and everything else but the way we gave four points away this week has rolled a very big stone in our way and it will take a lot of work to move it.
“It’s a disaster. We have to sleep the night over because at the moment it feels horrible. But maybe it will feel worse, not better, when we wake up in the morning.”
Southampton are next in action against Arsenal on 24th February, a team they got the better of 3-2 in the reverse fixture at St Marys.
The Gunners are 9/20 for the win, with Saints 11/2 and the draw 7/2.
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