Chelsea will face Manchester City in the FA Cup semi-finals, with Southampton facing Leicester in the other tie.
Both ties will be played at Wembley Stadium, with one on April 17 and the other on April 18.
The sides are playing for the right to take part in the 2021 final at Wembley on May 15.
How they got there
Southampton were the first side through into the semis thanks to a comfortable 3-0 win over local rivals Bournemouth. Moussa Djenepo got the opening goal eight minutes before the break, while a double from Nathan Redmond sealed their place in the last final four.
They were swiftly followed by in-form Manchester City, who earned a 2-0 win against Everton at Goodison Park. Ilkay Gundogan and Kevin De Bruyne were both on target for the Citizens.
On Sunday, Chelsea secured their place in the draw with a hard-fought win over Premier League strugglers Sheffield United. A first-half own goal from Oliver Norwood was finally added to by Hakim Ziyech, although Thomas Tuchel's side missed a plethora of opportunities to add to their advantage.
Leicester and Manchester United were level at 1-1 when the draw was made during half-time at King Power Stadium, but won through 3-1 in the end.
How do Chelsea and Man City shape up?
Chelsea have played Manchester City once previously this season. That was on January 3, amid City's record-breaking winning run. On that occasion, Pep Guardiola's men won 3-1.
Since then, however, Tuchel has taken charge of the Blues and has led them on a 14-match undefeated run.
Chelsea are actually 15 unbeaten in all competitions, with Frank Lampard's last match in charge a 3-1 FA Cup win over Luton.