One of Arsenal’s revamped systems failed but another just about held up. If this season is to be a sinew-straining exercise in keeping pace with Manchester City then they got the first step more or less right, although a late wobble from nowhere was a reminder nothing will come easy.

The home crowd, many of whom were stuck outside before the game due to problems at the turnstiles that delayed kick-off by half an hour, could breathe easily and reflect that their team had played enough of the hits to breed optimism.

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Bukayo Saka belted one out resoundingly and ensured Nottingham Forest, seemingly well beaten before a last-gasp flurry, faced too long a route back.

Arsenal had overcome a slow start to lead through Eddie Nketiah’s deflected shot when, six minutes later, William Saliba won possession in Forest’s left-back position. The ball was worked to Saka, who shrugged off Orel Mangala and bent in a vicious curler that Matt Turner had no chance of repelling. Saka looked jaded at the end of 2022-23, and was far from the only one, but this was Arsenal’s star attraction at his most compelling.

“An incredible finish,” said Mikel Arteta, although he was even more effusive about its more fortunate predecessor.

Nketiah had been widely expected to deputise for the injured Gabriel Jesus in last Sunday’s Community Shield and was stung when Kai Havertz was selected up front instead.

Arsenal were hogging the ball but failing to make many inroads when Gabriel Martinelli, if by accident more than design, pirouetted on the left side of the penalty area and backheeled to Nketiah in space. A drilled finish gave Turner, who had left Arsenal for Forest only three days previously, no chance and earned the scorer lavish plaudits.

“He is a role model,” Arteta said. “He was so disappointed not to play in the absence of Gabi. He came in the final and changed the game, that’s No 1. The second thing was the way he trained this week, saying: ‘Gaffer, if you’re not playing me you’re blind.’ He’s a clear example to everybody.”

Arteta had, as he admitted, set a precedent for the season by switching up his team. Gabriel Magalhães was moved to the bench, meaning Ben White tucked in at centre-back and Havertz adopted the attacking midfield role for which he has been signed. Thomas Partey’s movements infield from right-back meant that, for long periods, their formation was akin to 3-1-3-3.

It was Saliba’s failure to cut out a regulation header forward from Willy Boly, rather than any wider malfunction, that let Brennan Johnson in for a clear opportunity in the 11th minute. The Forest forward should have tested Aaron Ramsdale at the barest minimum; instead he sidefooted high and wide and it did not take a sage to understand the visitors would rarely happen upon such an appetising chance.

Soon enough they were all but out of the game, primarily kept in it by Arsenal’s inability to turn the screw. The first cloud on their afternoon came with an injury to Jurriën Timber, who had made a composed competitive debut at left-back but felt the effects of a first-half knock and pulled up five minutes after the interval.

Thereafter, proceedings took on a pre-season hue with surprising ease, Forest going through the motions of mustering extra threat on the rare occasions they were given an extended feel of the ball.

Declan Rice, a commanding presence if not always at his crispest, forced Turner to tip a deflected strike on to his left post and parry away a curious bobbled effort. But Arsenal were nowhere near full tilt and almost immediately after the latter allowed Forest to break from a corner.

The recently introduced substitute Anthony Elanga was able to carry the ball 70 yards up the left flank unopposed and centre for another replacement, Taiwo Awoniyi, to score emphatically.

The Emirates, snoozy since Saka’s blast, woke up and was almost aghast when Morgan Gibbs-White fired over. Perhaps seven minutes of added time felt relatively small beer given the fans’ earlier wait to enter the ground.

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Arsenal saw it out and Arteta praised the manner in which they did so, although he urged them to be “more ruthless and more critical of ourselves to be pushy and kill the game”.

His opposite number, Steve Cooper, was left to rue the mountain Forest had to climb. “I’m frustrated with the first half,” he said. “At half-time, we questioned ourselves in terms of competing. In the second half we showed a bit more quality and belief that we belong at this level. It then leaves a feeling of what might have been.”

Arsenal can sympathise with that sensation but will feel fully entitled to dream once more.