Four-star Man City, Crystal Palace into FA Cup semi-finals
Manchester City finally got the better of Southampton at the third attempt this season with a 4-1 win to move into the FA Cup semi-finals on Sunday.
Crystal Palace also hit four to thrash struggling Everton 4-0 to make the last four.
City's bid to retain their Premier League title has been hindered by two draws against the Saints and Ralph Hasenhuttl's men held their own again for an hour at St. Mary's.
Adam Armstrong nearly made the most of a rare start when he hit the post early on for the home side.
But just seconds later Raheem Sterling opened the scoring with a cool finish from Gabriel Jesus' pass.
Ilkay Gundogan then hit the woodwork, but Southampton got the equaliser their first-half performance deserved when Aymeric Laporte deflected Mohamed Elyounoussi's cross into his own net.
With the tie delicately poised, the Saints' good work was undone when Mohammed Salisu needlessly dived in on Jesus to concede a penalty.
Fraser Forster got a hand to Kevin De Bruyne's spot-kick but could not keep it out.
City's strength in depth off the bench then took the game away from the hosts as substitutes Phil Foden and Riyad Mahrez produced lethal finishes to give the scoreline a harsh reflection on Southampton.
Vieira's Palace progress
Earlier, Palace stormed into the last four for the first time in six years by seeing off sorry Everton.
Marc Guehi, Jean-Philippe Mateta, Wilfried Zaha and Will Hughes got the goals as the Eagles continued their impressive first season under Patrick Vieira.
"Going to Wembley is fantastic," said Vieira.
"You can hear the atmosphere in the stadium, the fans; this is what they wanted and we wanted to give it to them."
Everton's focus now turns to just staying in the Premier League as they sit perilously just above