Onuachu netted the decisive goal three minutes from time in the battle of the division's bottom two sides.

Southampton broke the deadlock in the 21st minute when Mateus Fernandes's deflected cross fell kindly for Joe Aribo, with Arijanet Muric only able to help his volley into the net.

Ipswich responded just after the half-hour mark with Liam Delap darting in behind to beat Jan Bednarek to a loose ball, and calmly slot past Aaron Ramsdale.

It looked like the spoils would be shared, but there was to be a late twist, with Onuachu pouncing on the rebound of Kamaldeen Sulemana's saved strike to snatch the visitors' first away league win of the campaign.

Juric's side remains bottom of the table but moved seven points behind the hosts, who remain 19th after missing the chance to climb out of the relegation zone.

Ipswich manager Kieran McKenna acknowledged the defeat at home was an opportunity missed in terms of bolstering his side's survival hopes.

"No doubt [that it is a missed opportunity], it's a bad result for us," he said. "[A] poor way to lose the game.

"We were the better team, had the better chances, should have been ahead, should have killed the game, but didn't and then lost it to a poor late goal from our point of view."

McKenna was also disappointed at another late goal being conceded by his side at Portman Road, with the likes of Leicester and Bournemouth punishing his side in a similar manner earlier in the season.

"It's an opportunity missed," he added. "Another home game that we have lost late, and we have had too many of those.

"We've got 14 games left to try and make sure we write a different story for our season and, hopefully, we're not talking at the end about the disappointment of conceding late goals, and letting points go adrift."

Meanwhile, Southampton boss Juric revelled in a "great feeling" after picking up his first win in the Premier League, despite his side still being rooted to the bottom of the table.

"The guys deserved it because they worked a lot," he said. "They played some good games and we lost, but today we won. The character is always there. We will enjoy tonight, that's for sure, it's a great feeling.

"We've won today and I think the team can improve themselves and make good matches, and think that we can do something really special. That's our idea. We have to have good character and improve every game."

The Croatian also praised the performances of debutants Wellington and Albert Gronbaek, who helped contribute to the Saints' first league win since November and a first away victory in the top flight in 20 attempts.

"I think they gave us a hand," he added. "Welington had a really good game, he was very tired because he hadn't played for six months. And Albert, his technique, he had some opportunities in the first half."