Mark Hughes bemoaned the award of a "very soft" stoppage-time penalty as Southampton surrendered a two-goal lead to draw 2-2 with south-coast rivals Brighton.
Albion striker Glenn Murray converted the late equaliser after referee Anthony Taylor pointed to the spot following James Ward-Prowse's tangle with Shane Duffy.
Pierre Hojbjerg's long-range strike and a penalty from Danny Ings looked to have put Saints on course for successive Premier League wins for the first time since April 2017.
But Brighton showed resilience to pick up their first away point of the campaign after Republic of Ireland defender Duffy headed in with 23 minutes remaining to start the fightback.
"He's a big boy, the big centre-half, and has gone down a little bit easy and the referee's decided that warranted a penalty decision at that late stage," Saints manager Hughes said of Duffy.
"That was a shame.
"We go zonal (marking). He (Ward-Prowse) is there as a blocker, you have to block.
"That's what he basically did. He hasn't tripped him up or thrown him to the ground; it would have been very difficult for Ward-Prowse to throw him to the ground.
"It was a very soft penalty and unfortunate but sometimes referees go with what they see in the split second."
Saints, who won at Crystal Palace before the international break, have struggled at St Mary's.
Victory would have been just their fifth from their last 27 top-flight fixtures in front of their own fans.
Hughes felt his players should have seen the game out.
"You just have periods in games where momentum goes against you," he said.
"You have to ride out those moments and hope you don't concede.
"At the end of the day, you've got to give them (Brighton) credit.
"They had nothing to lose, they were 2-0 down. They thought: 'Sod it, let's have a go, throw people forward and take risks.'
"We're disappointed because we should have been home and hosed long before the 92nd minute, or whenever it was when they got the penalty award."
It was the second successive match that Brighton fought back from two goals down to draw 2-2 following their home game against Fulham at the start of the month.
Albion boss Chris Hughton praised the desire of his players to turn the game around following a lacklustre first-half display.
"If our performance second half was the same as the first half, then I think we're struggling," said Hughton.
"But we certainly upped the intensity of the game, pressed better, and broke really well.
"I was confident we would create chances. Once we got one back, if someone was going to score, I felt it was going to be us.
"I can say what I need to say, and shout as much as I want, but you've got to have a group of players who realise it themselves.
"There wasn't a player coming in at half-time who didn't realise the team had under-performed. And you can't do it in this division and get away with it.
"Credit to them, they upped their game."
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