At Sporting Clube de Portugal, change is the only constant. Just four months after José Peseiro was tasked with leading the club out of the chaos of Bruno de Carvalho’s doomed presidential reign, he has been sacked, with Sporting third in Liga NOS and just two points off the top.

Fittingly, Peseiro met his fate shortly before midnight on Halloween. “We know where we are and where we want to get to,” he had bullishly insisted after a 1-0 loss to Estoril in the League Cup. Presumably he hadn’t been talking about the Job Centre. Just a few hours later and he had been relieved of his duties.

And so Sporting’s shambolic summer — which saw players attacked and injured in an attack on the club’s training ground by masked men, ultimately precipitating De Carvalho’s downfall — extends into the winter months. First Sinisa Mihajlovic was fired just nine days after his appointment at the start of the season. Now Peseiro has fallen. His assistant, the inexperienced Tiago Fernandes, is the latest to be offered up at the managerial altar.

Once again, Arsenal find themselves the beneficiaries of Sporting’s chaos. They travelled to Lisbon just a few days after Sporting’s players had been booed from the pitch after a poor performance against lowly Loures in the Portuguese Cup, prevailing thanks to a late goal from Danny Welbeck. Another win tonight would see them guarantee top spot in Europa League Group E.

Sporting vs Arsenal Show all 11 1 /11 Sporting vs Arsenal Sporting vs Arsenal Bernd Leno - 7 Bernd Leno: 7 out of 10 - A fairly quiet night for the German, but he dealt with what he needed to. There were some shaky moments as the Gunners looked to play the ball out from the back in the first half, but Leno and the defence just about got away with them. A clean sheet. AP Sporting vs Arsenal Stephan Lichtsteiner - 7 A quiet night for the Swiss international, who was back at right-back this evening. Nani felt he should have been penalised in the first half after a tussle between the pair in the Arsenal box. The former Juventus man did well to deliver some dangerous crosses when the away side were pressing for an opener in the second half. Getty Images Sporting vs Arsenal Sokratis Papastathopoulos - 6 The centre-back was perhaps lucky to have not been sent off in the first period after a tussle with Fredy Montero. Both he and Holding did well to deny Sporting from creating much in the first half but there were a few unconvincing moments as the away side looked to play out from the back. EPA Sporting vs Arsenal Rob Holding - 6 The former Bolton man was guilty of a terrible pass out from the back in the first half which nearly cost his side, but he defended well when he had to. It will be interesting to see if he keeps his place in the Gunners’ league tie with Crystal Palace on Sunday. Action Images via Reuters Sporting vs Arsenal Granit Xhaka - 5 It’s fair to say that Granit Xhaka is not a left-back. He wasn’t disastrous tonight, but he didn’t look too comfortable. His set piece delivery was very poor. Unai Emery will be hoping either Nacho Monreal or Sead Kolasinac return to fitness soon. REUTERS Sporting vs Arsenal Aaron Ramsey - 7 Ramsey started in a slightly more withdrawn midfield role tonight and struggled to support striker Aubameyang before the second period. The introduction of Torreira saw him push on. It wasn’t his busiest night, but he didn’t do a lot wrong. Action Images via Reuters Sporting vs Arsenal Matteo Guendouzi - 7 The youngster continues to impress. He was particularly influential in the second half. The introduction of Torreira helped him and gave him more license to try and effect the game in the final third. AP Sporting vs Arsenal Mohamed Elneny - 6 Elneny didn’t do a lot to put his case forward for a regular starting spot. He was the first player that Emery chose to withdraw, with his replacement Lucas Torreira having a big effect on the game in the second half. Action Images via Reuters Sporting vs Arsenal Henrikh Mkhitaryan - 6 The Armenian was forced into a lot of defensive work in the first half, with Sporting left-back Acuna bursting forward to join the attack whenever he could. Mkhitaryan didn’t look partiulalry keen on having to track back so often, but he did his job. In the attacking third, he had more of an effect on the game in the second half. Getty Images Sporting vs Arsenal Danny Welbeck - 8 The match winner. Welbeck finished well after former Liverpool defender Sebastian Coates made a poor error. He started in a role on the left hand side but got a lot closer to Aubameyang in the second half. His strike tonight was his fifth goal of the season. Not bad. Action Images via Reuters Sporting vs Arsenal Pierre-Emerick Aubameyang - 7 Not the liveliest of evenings for the Gabon striker. He had a couple of good chances to open the scoring in the second half but was denied by Sporting goalkeeper Ribeiro. Will he start against Palace at Selhurst Park on Sunday? We shall see. Action Images via Reuters

Chances of an upset appear slim. Arsenal’s impressive draw with Liverpool last Saturday saw them extend their undefeated run to 14 matches, some three months after they suffered back-to-back defeats to Manchester City and Chelsea. Sporting are meanwhile struggling for form, losing two of their last four.

And yet in the club’s first performance under Fernandes — a comeback victory away from home against Santa Clara, on Sunday — it was possible to detect some tentative green shoots of recovery. Trailing 1-0 after an hour, Dutch striker Bas Dost levelled the score from the penalty spot, before the Argentinian Marcos Acuña crowned an impressive performance with a header to win the game late on.

Sporting will need both to be at their best at The Emirates tonight. Particularly Acuña, who has really caught the eye for Sporting this season out on the left and was a constant threat to Arsenal’s backline in Lisbon. The 27-year-old only moved to Europe last season, immediately adjusting to his new surroundings and attracting the interest of several Premier League clubs.

“I first saw Marcos playing for Ferro, a small team in the second tier of Argentina, and the first thing I noticed about him was his temperament, his personality,” says Diego Cocca, who was Acuña’s coach at Racing Club, in an interview with The Independent.

“Obviously he has got a lot of quality in footballing terms. He’s got an unbelievable left foot, a rocket of a shot and he is so fast and strong. But that mental strength was a big part of who he is, and it’s why he has made the step up easily at every level.”

Step up he has. From Argentina’s second tier with Ferro he moved to Racing, one of the country’s ‘big five’.

Acuña impressed against Arsenal (Arsenal FC via Getty)

After helping Racing to their first league title in 13 years that same season he arrived, Acuña would eventually depart for Sporting but the step up to Europe was similarly something he took in his stride.

“Despite jumping up a division, and arriving at a big, big club, I had faith that he was so competitive within himself that he would fight to make the jump up and he surprised everyone with how quickly he adapted.

“We had the expectation that he would succeed and clearly when he went to Europe we knew similarly that he would have that same success.”

And while attacking players from Argentina, in particular those charged with playmaking responsibilities, have a reputation for drifting in and out of games or being generally a little bit soft, Acuña has a feistiness and determination that makes him a different proposition to Sporting’s other big dangerman, Portugal’s Bruno Fernandes.

Peseiro was sacked last week (Getty)

“The strongest thing he has is his spirit, his mentality and his commitment to improve himself. He never backs down and whenever the game is going against you he will always fight to turn it around, even when there is no time left.”

Sporting have other players who can hurt Arsenal — in-form or otherwise. Dost is finally back to full fitness after a long stretch out with a muscle injury, while former Manchester United man Nani came close to catching Bernd Leno out in the first match against Arsenal with a speculative effort from distance.

Not that losing tonight would prove terminal to Sporting’s hopes of reaching the knockout stages — even without a manager they are hardly likely to slip up against the utterly inadequate Vorskla Poltava and Qarabag. But they did enough in the first match to suggest that they have a chance of causing an upset — particularly if Emery is too bold in his team selection.