Mourinho was sacked earlier in the week after losing the faith of the United dressing room with his snide remarks to the media and negative playing style.
Former United striker Ole Gunnar Solskjaer was named interim manager until the end of the season while Old Trafford executives seek a new permanent head coach.
The Norwegian vowed to restore the fundamental attacking values at United, which revolve around attacking football and hard work, and was rewarded early on in Cardiff when Marcus Rashford laced home a free-kick from 25 yards.
Ander Herrera doubled the Red Devils’ lead on the half-hour mark and Victor Camarasa’s penalty was deemed irrelevant when Anthony Martial and Jesse Lingard (twice) etched their names on the scoresheet.
eams really ought to be able to play a Mourinho joker card if they have not faced United under his management
Alyson Rudd
As 1,800 United fans sang jubilantly in the stands, supporters from around the world took to Twitter in order to voice their love for Solskjaer and - more notably - slam their dismissed manager.
Leading 3-1 at half-time, one fan reacted: “I literally cannot believe what I’m watching. Mourinho is a sick b*****d I swear.”
In reference to The Special One’s media antics, another supporter tweeted: “Mourinho killed these lots confidence.
“Constantly calling them s***e in public. I wouldn't want to work properly in that kind of environment.”
Manchester United fans have trolled Jose Mourinho following their first win under Solskja (Image: Getty)
Manchester United caretaker boss Ole Gunnar Solskjaer was delighted with his side's performance (Image: Getty)
Invalid email
We use your sign-up to provide content in ways you've consented to and to improve our understanding of you. This may include adverts from us and 3rd parties based on our understanding. You can unsubscribe at any time. Read our Privacy Policy
Another reflective United fan simply asserted “We got our club back,” while one jovial member of the Old Trafford faithful joked “You gotta go to Mourinho’s house and sack him again @ManUtd.”
Some print journalists were also quick to point out how different United looked after just two days under Solskjaer.
The Times’ Alyson Rudd joked: “Teams really ought to be able to play a Mourinho joker card if they have not faced United under his management.
Jose Mourinho even copped some stick off national print journalists (Image: Twitter/allyrudd_times)
Jose Mourinho made CLASSY gesture after sacking says reporter
Manchester United players celebrate their 5-1 win (Image: Getty)
“Not fair on Cardiff all this joyous football.”
Meanwhile, Manchester Evening News journalist Samuel Luckhurst opined: “Does reflect damningly on Mourinho and #mufc players that, within two days of the new coach arriving at Carrington, they can play like they did…
“Mourinho may not have preached football this cavalier but some players clearly downed tools and cost the team points.”