Arsenal had been delayed by one storm in the buildup to this tie and then, on a night that may have graver consequences, wilted under another.
The celebrations at full time showed how much this meant to Lens, who responded superbly to a ferocious atmosphere and played with tempo and intelligence that merited their win. It was a sharp reminder for Mikel Arteta’s players that progress to the round of 16 cannot be taken for granted but they left wondering whether that was the only damage incurred.
There had been suggestions Saka might be rested here after sustaining a number of knocks in recent weeks, most recently a blow to the foot at Bournemouth, but he showed up again because that is what he always does. Saka plays on, keeps going, takes a buffeting but invariably outshines almost everyone; the fact he felt it necessary to depart so early, then, was cause for real alarm.
Arteta explained his talisman had “felt something muscular” and, with a vital Premier League assignment against Manchester City coming up, was left hoping for good news in the morning.
“He felt uncomfortable to carry on so we had to take him off,” Arteta said. “We don’t know anything more. It was big enough not to allow him to continue to play the game and that’s a worry for us.”
Perhaps the match had been ill starred for Arsenal since Monday evening, when inclement weather left them waiting five hours to make the short hop from Luton airport. But Arteta knew that was no excuse: ultimately they could not respond to the intensity mustered by a Lens team, roared on by a crowd that kept the energy up throughout, that raged with intent in their first Champions League game here for 21 years.
It felt from the start that Arsenal had been pitched into a furnace, four pulsating stands of red and yellow shirts leaving no doubts about the importance of this occasion to a proud coal-mining region. Heat and noise radiated from the terrace of ultras that flanked an entire side of the pitch. “Together we will shine our coat of arms in the Champions League,” was emblazoned on a banner at kick-off.
Arsenal would have to win the duels but early on, as Kevin Danso shot wide and Facundo Medina barrelled his way through three challenges, there were clear signs that this was almost a different sport to their cakewalk against PSV Eindhoven. Perhaps they expected Lens might burn themselves out and, when the home side’s first real moment of sloppiness was punished clinically, that felt a reasonable assumption.
A sloppy backwards pass from Thomasson was seized upon by Saka, sharp and mobile as ever at that point, and quickly spirited to Gabriel Jesus. There was still work to do but, advancing towards the penalty area and creating half a yard, the Brazilian arrowed a perfect low drive across Brice Samba. The home support kept singing but the fire appeared to have been doused.
“We were in total control at that moment,” Arteta said. Samba saved a Kai Havertz volley but, with Arsenal searching for a second, they were caught out. David Raya is feted for slick distribution but his ball out to Takehiro Tomiyasu was seized on by the left-wing-back Deiver Machado, who searched for Elye Wahi up front. The execution from there was magical, Wahi controlling and flicking gymnastically to Thomasson for a marvellous half-volley that ensured full redemption for the scorer.
Saka left the stage soon afterwards, to be replaced by Fábio Vieira, and Arsenal scratched their way to the interval. Leandro Trossard missed a chance to restore their lead soon after the restart and Lens, regaining a serious attacking threat either side of the hour, ultimately capitalised. An unmarked Tomiyasu had just shot at Samba unmarked when Przemyslaw Frankowski surged into the space beyond Oleksandr Zinchenko and squared for the 20-year-old Wahi, a £30m signing from Montpellier who was outstanding throughout, to sweep in.
“Big teams punish you,” Arteta lamented. “We defended the box really poorly.” Reiss Nelson, a substitute, almost squeezed a late shot past Samba and there was late chaos when Raya came up for two corners. Arsenal, though, could have no complaints at being caught out and Lens’s players were able to milk the cheers long after the end. Arteta generously remarked it had been “great to embrace that moment and play in the atmosphere”, but his memories will be heavily clouded.