Manchester United will host Liverpool in an FA Cup quarter-final blockbuster after the bitter rivals took contrasting routes to their fifth round victories on Wednesday.

United eased the pressure on beleaguered boss Erik ten Hag as they scraped through with a 1-0 win at Nottingham Forest thanks to Casemiro's late goal.

Fresh from their League Cup final triumph against Chelsea on Sunday, Liverpool relied on their youngsters again in a 3-0 win against second tier Southampton at Anfield.

Chelsea bounced back from their painful 1-0 defeat to Liverpool at Wembley, snatching a 3-2 win against Championship promotion chasers Leeds to book a last eight date with Leicester.

After Liverpool's ball boys paraded the League Cup around Anfield prior to kick-off, Jurgen Klopp's kids gave another glimpse into a bright future as two of their young guns inspired the win.

With Liverpool ravaged by injuries to Mohamed Salah, Darwin Nunez, Diogo Jota and Alisson Becker among others, Lewis Koumas, the son of former Wales and West Brom midfielder Jason Koumas, marked his debut with the opening goal in the 44th minute.

The 18-year-old forward drilled a fierce low drive that deflected in off Southampton's Jack Stephens.

Jayden Danns, another 18-year-old offspring of a former player -- his father Neil starred for Crystal Palace -- netted Liverpool's second in the 73rd minute with a composed finish that belied his tender age.

James McConnell, 19, and Bobby Clark, 19, also impressed for Liverpool, who introduced 16-year-old Trey Nyoni to become their youngest ever FA Cup player in the second half.

Danns capped the victory in the 88th minute when he lashed home in front of The Kop.

At the City Ground, United reached the FA Cup quarter-finals for a record 48th time.

Ten Hag insisted this week that he doesn't need a public vote of confidence from Jim Ratcliffe after the British billionaire took charge of United's football operations.

But United are languishing in sixth place in the Premier League, eight points adrift of the top four, after Saturday's shock 2-1 home defeat against Fulham.

A loss to Forest would have been a major blow for Ten Hag after Ratcliffe was linked with a move for former Real Madrid boss Zinedine Zidane.

The FA Cup represents United's last silverware chance this term and, after missing a host of chances, they finally hit the target in the 89th minute when Bruno Fernandes' free-kick was headed in by Casemiro.

Ten Hag will hope a 1-0 FA Cup win at Forest proves a launchpad for sustained success at United in the same way it did for former boss Alex Ferguson in 1990.

At Stamford Bridge, Mauricio Pochettino will have felt similar relief to Ten Hag.

With the pressure mounting in his troubled first season in charge, the Argentine was indebted to Conor Gallagher for a late winner.

It was the first FA Cup tie between Chelsea and Leeds since the Blues won the 1970 FA Cup final replay, a booking-filled clash regarded as one of the most vicious matches in English football history.

Chelsea fell behind after just eight minutes when Mateo Joseph fired home for his first senior goal.

Nicolas Jackson dragged Chelsea level seven minutes later, driving his shot through the legs of poorly-positioned Leeds keeper Illan Meslier.

Mykhailo Mudryk swept Chelsea ahead in the 37th minute with a clinical finish into the far corner.

Joseph equalised after 59 minutes with a close-range finish from Jaidon Anthony's cross.

But Gallagher won it in the 90th minute, lifting his shot over Meslier to make partial amends for missing a host of chances in the League Cup final.

Elsewhere, Wolves beat Brighton 1-0 at Molineux, with Mario Lemina's goal after just 77 seconds securing a home tie against second tier Coventry.