Manchester United will experience far stiffer tests of their Champions League credentials than Sabah FK gave them at Old Trafford.

In fact, it would be no surprise if the Azerbaijan champions were by some distance the weakest of the eight league stage opponents Michael Carrick’s side will come up against.

However, there were some important lessons for Carrick to absorb.

The biggest of them is United are a much more effective unit when Benjamin Sesko starts.

This was the first time the Slovenian had done that since the Liverpool game last March, when he finally accepted he could no longer play through the shin issue that had been plaguing him for a number of weeks.

It had been hoped Sesko would be fit for the start of the Premier League season.

As it turned out, he was only at the stage where he could be brought on as a substitute in the second half of the opening day trip to Hull. The same also applied for the subsequent outings against Ipswich and Everton.

It was Sabah FK’s bad luck Sesko was fit to start against them – and it showed.

At 6ft 5in, the 23-year-old has a physical presence United’s other strikers lack.

While it has been unfortunate Amad Diallo’s current absence has robbed Carrick of the option to start Bryan Mbeumo at the head of his attack, as he did during pre-season, Matheus Cunha is not without ability.

The problem is the Brazilian likes to drift and drop back into space, which leaves a gap at the apex of Manchester United’s attack.

Sesko offers a totally different threat. He pushes defences back. He is not easy to dispossess. He runs at opponents rather than away from them.

He also scores goals.

At Everton, it was his size that allowed him to convert a close-range header that should have given United victory but didn’t.

Against Sabah FK, he had already threatened with an impudent first half back flick when Bryan Mbeumo sent him running beyond the visitors’ defence.

Sesko had clarity of thought, swiftly moving the ball past goalkeeper Stas Pokatilov before steering the ball into an empty net.

“Of course, I’m happy with my goal,” Sesko told TNT.

“I saw him rushing out, and it was a great opportunity to take the ball away from him and make the goal a little bit easier.”

It’s not that Mbeumo and Cunha can’t do that, it is more that Sesko can do it in addition to presenting the physical threat.

Good control for a big man is one of football’s oldest cliches. Yet the players who can combine size with skill and pace are exceptionally useful.

“He definitely offers a different kind of threat,” said Carrick.

“That’s the beauty of it, really. We know what Ben gives us. There’s not many around that kind of give you what Ben does in terms of his physique, his physicality, playing on the last line and his speed to run in behind. He’s a real threat.

“It’s great to have him back at this level after working to get his fitness back.

“A couple of goals and good performances, and good minutes in him. I’m really pleased with the way he’s gone.”

Who starts against Man City?

It is a fairly obvious thing to say but Carrick now has a big decision before Sunday’s derby clash with Manchester City at Old Trafford.

Does he trust Sesko’s fitness and stick with him? Or does he revert to Cunha, given there has been no indication Amad is ready to return.

On this evidence, Sesko should get the nod. That in turn would leave Carrick to decide whether Cunha, who opened the scoring, or Marcus Rashford, who was an unused substitute, should start on the left.

Rashford is yet to score a goal or create one since he returned to his boyhood club.

However, he has been their most consistent threat with his pace and direct running.

Cunha drifts into similar positions to skipper Bruno Fernandes.

Carrick may decide United’s structure works better with the England international.

If that is the case, he wasn’t admitting it on a night when Fernandes also scored.

“It’s not an easy decision, of course it’s not,” he said of his team selection.

“But it’s definitely one I’d prefer; to have goals in the team and for the boys to be playing well.

“The understanding they all have, is that sometimes it’s going to be a start, sometimes it’s going to be finishing the game. We need that within the group, from game to game over the season, to be able to call upon slightly different kind of things at different times.

“It’s fantastic they’re all in good form and started so well.”