Manchester United started life without Jose Mourinho with a stylish and energetic display under Ole Gunnar Solskjaer as they thrashed Cardiff 5-1.
Goals from Marcus Rashford (3), Ander Herrera (28), Anthony Martial (41) and a second-half double from Jesse Lingard (64, 90) saw United score five goals in a Premier League game for the first time since Sir Alex Ferguson departed.
After the negative performances under Mourinho, Solskjaer seemed to give his players a freedom to express themselves and was rewarded with a scintillating attacking showing, spearheaded by Martial, who looked especially rejuvenated, as did Paul Pogba.
Cardiff, who had won their last three home games, were completely outclassed and could only muster a penalty from Victor Camarasa (38) in response to United's silky and exciting showing.
Cardiff: Etheridge (3), Bamba (5), Manga (5), Morrison (5), Cunningham (5), Arter (5), Gunnarsson (3), Camarasa (6), Murphy (3), Hoilett (5), Paterson (5).
Subs: Zahore (7), Harris (5)
Manchester United: De Gea (7), Shaw (7), Lindelof (7), Jones (7), Young (7), Matic (8), Herrera (8), Pogba (8), Lingard (9), Rashford (9), Martial (9).
Subs: Fellaini (N/A), Pereira (N/A), Fred (7)
Man of the match: Anthony Martial
United made the perfect start when Pogba won a free-kick after a neat one-two and Rashford stepped up to blast home a swerving effort from 30 yards.
Pogba played a part in the second goal, too. The World Cup winner - out in the cold under Mourinho - found Herrera with a clever ball and the Spanish midfielder's effort from 25 yards took a deflection off Greg Cunningham and flew into the top corner.
Solskjaer made four changes from Mourinho’s last game in charge against Liverpool. Luke Shaw, Paul Pogba, Phil Jones and Anthony Martial all were handed starts. Romelu Lukaku was away on compassionate leave. There was just one change for Neil Warnock’s men as Greg Cunningham replaced Joe Bennett.
Cardiff quickly got themselves back into proceedings as Rashford was adjudged to have handled in the box, which provided Camarasa with a chance from the spot, one that he took.
However, the Cardiff goal only triggered United to step it up another gear. Martial, Pogba and Lingard linked brilliantly just outside the box and Martial galloped through before finishing into the far corner.
United continued to attack after the break and Lingard was brought down in the box as he tried to dribble past Sol Bamba and Sean Morrison. Lingard confidently netted from the spot.
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Four was not enough for the visitors as they pressed on and Pogba slipped in Lingard with one of the last attacks to cap a dream start to Solskjaer's tenure.
Man of the match: Anthony Martial
This style of football suits the Frenchman, who was in his element with the attack-minded football that Solskjaer obviously demanded. Unlike his recent performances this season, every touch he took was a positive one which put the Cardiff defence on the back foot from the first whistle. His excellent goal summed up United's new approach. It was slick, quick and full of quality.
- Manchester United scored 5+ goals in a Premier League game for the first time since Sir Alex Ferguson's final match in charge, in May 2013 against West Brom (5-5).
- Since Sir Alex Ferguson left the club, four of the five different managers to take charge of Manchester United have seen their side score 3+ goals in their first Premier League game (Moyes 4, Mourinho 3, Giggs 4 and Solskjaer 5).
- Cardiff have lost each of their last 14 Premier League games against 'big six' opponents, conceding 45 goals in this run.
- Martial has been directly involved in 70 goals for Manchester United in all competitions (45 goals, 25 assists); the most of any player for the club since his debut in September 2015.
- Rashford has had a hand in more Premier League goals this season than any other Manchester United player (9 - four goals and five assists).
Manager reaction: Ole Gunnar Solskjaer
"The attitude and application of the boys when you go out there and see them, the attitude has been fantastic, the dressing room, the way they approached this game.
"It's been a difficult week for everyone and to get the focus and perform as well as they did [is impressive]."
Manager reaction: Neil Warnock
"We need to stop conceding elementary goals. At any level, that first goal was terrible. It knocked us down. We were bound to get knocked down. We were playing against a top side with a new manager and all that comes with that. I was disappointed with the goals today, not the effort."
United are back at Old Trafford on Boxing Day when Huddersfield will be the visitors, while Cardiff take on Crystal Palace at Selhurst Park.