Manchester United 5-2 Galatasaray: Zlatan Ibrahimovic scores bicycle kick four minutes into debut with Wayne Rooney, Marouane Fellaini and Juan Mata also on target

Even Eric Cantona and Cristiano Ronaldo didn't make an impact for Manchester United as quickly as Zlatan Ibrahimovic in Gothenburg on Saturday night.

The Swedish heavyweight took just three minutes and 15 seconds to mark his United debut wtth a trademark stunning goal to get Jose Mourinho's pre-season plans back on track with a thrilling 5-2 victory against Galatasaray.

Antonio Valencia's cross from the right appeared to be travelling behind Ibrahimovic on the penalty spot until the 34-year-old launched himself in the air and connected with a fantastic overhead kick past startled goalkeeper Fernando Muslera.

MATCH FACTS AND RATINGS 

Manchester United: De Gea 6.5 (Romero 67 6), Valencia 8 (Darmian 67 6), Bailly 6 (Jones 67 6), Blind 6 (Rojo 67 6), Shaw 6.5 (Memphis 67 6), Schneiderlin 6 (Fellaini 45 6.5), Herrera 6 (Carrick 45), Mkhitaryan 5.5 (Lingard 45 6), Rooney 7 (Mata 7), Martial 6 (Young 45 6); Ibrahimovic 7 (Rashford 45 7.5)

Goals: Ibrahimovic 4, Rooney 55, 58 (pen), Fellaini 62, Mata 67

Booked: Rooney 

Galatasaray: Muslera, Linnes, Chedjou, Hakan, Carole, Selcuk, Dzemaili, Yasin, Sneijder, Bruma, Sinan (Sabri 84)

Subs not used: Cenk, Eray, Salih, , Gokay, Birhan, Berk Ismail, Emrah, Donk

Booked: Sneijder

Goals: Sinan 22, Bruma 41

It lifted United spirits in an instant after three turgid years under David Moyes and Louis van Gaal.

And the feelgood factor was further raised when Wayne Rooney, playing as a No 10, scored twice in the second half in his first outing since Euro 2016.

Ibrahimovic, signed as a free agent from Paris St Germain, was the undoubted star though as his compatriots chanted 'Zlatan, Zlatan' during the 45 minutes he was on the pitch.

'It was a good start and fantastic to score my first goal for United in Sweden,' he said. 'I had good support. This is my country. It is impossible to fail in my country.'

Worryingly for United's Premier League rivals, Paul Pogba should be coming soon as well in a world-record £100million deal.

'There's something great being built here,' added Ibrahimovic. 'If Pogba comes, it will be more interesting. Let's see.'

This was an important game for Mourinho despite its status as a friendly. The recent tour of China had not gone well with a 4-1 defeat against Borussia Dortmund and a wash-out versus Manchester City.

The new United boss started with his strongest available line-up before making 11 changes to give the rest a run-out.

It provided important clues to the way he will set up this season; 4-2-3-1 with Rooney behind Ibrahimovic and Anthony Martial and Henrikh Mkhitaryan either side.

Marcus Rashford came on as a half-time substitute and made an explosive impact as United came from 2-1 down at the interval.

'The players needed to play,' said Mourinho afterwards. 'Marcus did well and Ibra showed glimpses of what he can do.

'To train against opposition like this is the best we can do. I'm really happy with the mistakes we made as we can work on them.'

Rooney played alongside Ronaldo and Carlos Tevez when United were in their pomp winning the Champions League of 2008. He has occasionally fretted about the club's lack of ambition since but can't do that anymore. Like everyone else, he seems intoxicated by Ibrahimovic's charisma as well as his talent.

'He is a fantastic player and showed what he is capable of doing,' said the United captain. 'It was a great goal and I am sure there will be many more moments like that from him

'We have seen him do special things throughout his career and I am sure he will do that for us through the season. It's a great signing for us with his experience and he's been successful wherever he is been. Hopefully he will be for us as well.

'He's a nice fella, a normal guy. He gets on well with everyone, certainly on the pitch with the aura he brings with him.'

Just as significantly, Rooney knows where he stands with Mourinho, who he wanted to play for three years ago under Chelsea.

Having finished last season in midfield for club and country, the new manager has made it clear 30-year-old Rooney will only be considered as a first or second striker this season.

On night, he was used as a No 10, behind Ibrahimovic and then Rashford. After a difficult first 45 minutes in which he looked rusty, Rooney wasn't one of the five changes made by the manager, and improved drastically to score twice in three minutes.

'The plan was always for me to stay on in the second half. The important thing was the minutes. Of course you want to win, but the important thing is getting fit for the start.

'The manager has already told you and he's told me I will be a No 10 and when I play in that position I know I will score goals.'

Amidst all the plaudits, Mourinho will know there is still a lot of work to do defensively. After Ibrahimovic's opener, the United defence – minus the injured Chris Smalling – went to sleep to allow Sinan Gumus and Bruma to put the Turkish club ahead at the interval.

Rooney levelled when he broke forward to volley in Valencia's cross, one of three assists for the Ecuadorian. Then, the United skipper released Rashford with an outstanding pass and the teenager put on the turbo-chargers to win a penalty which Rooney smashed in.

Valencia set up Marouane Fellaini for a header to make it 4-2 after 62 minutes and after Rooney had been withdrawn, Juan Mata burst into the area like a fox in the box to convert Michael Carrick's cross.

Rooney will have his testimonial against Everton on Wednesday night before United play Leicester in the Community Shield on Sunday. Pogba may have arrived by then, while others like Bastian Schweinsteiger and Adnan Januzaj know their race is run having been left in Manchester this weekend to train with the under-21s.

Above all, the Zlatan effect is taking grip. With league titles already in Italy, Spain, Holland and France, he'll be looking for the Grand Slam this season, and the youngsters are already in awe.

'It's a massive help being with him day-in, day-out,' says Rashford. 'He's been amazing.'

All this after a few days training and 45 minutes. What's next.