The crisis on Sunday is the beacon of hope on Thursday. A visit to one of the more celebrated teams in a competition, which they preferred not to prioritize, did not seem to be a promising vehicle for Arsenal, as they were so fought over after the bad road they had lost in Watford that it turned into best possible advertising for their best minded adolescents.

18-year-old winger Bukayo Saka scored an excellent second goal with his first and third goals. Joe Willock, a team of midfield inventions, broke the stalemate before the break on an evening that showed Arsenal's ability to switch between optimism and despair.

Umai Emery's child prodigy managed to defeat a venue that devours its continental football hungry. Eintracht fans had filled the stadium to watch opponents like Flora Tallinn and FC Vaduz during qualifying rounds. The mood they are playing, in a sense, explains a run of 16 unbeaten home matches in European competition dating back to 2006.

So it was a Petri dish where Emery experimented with Saka and Emile Smith Rowe. The teenage strikers had six older starts between them, but flanked Pierre-Emerick Aubameyang, who was one of four survivors on the start line in Vicarage Road. Willock, who turned 20 last month, was hired to stand behind them, and it was a mix that could go horribly wrong under the current conditions as things dissipate.

Such thoughts seemed irrelevant at the end of an extended, wavering first half. For Arsenal, the crucial point was Willock's goal in the 38th minute and they had already missed three easier chances. Their first meaningful attack resulted in Saka trimming a well-weighted left-handed shot and Lucas Torreira, who was starting at the far post but taking just half a volley after seven meters, should have rewarded his good work.

Shortly before half-hour Willock seemed to have missed his big chance when he met Aubameyang's center and could only overtake him if he was well placed. There was still time for Smith Rowe, who completed a clean pass from Granit Xhaka and was defeated by Kevin Trapp before Arsenal scored the first.

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It happened after another single-minded arrow passed from Saka to Willock, and his teammate flew in before letting go. The ball flew over a big rebound from David Abraham and a rebound from the crossbar into the net, but Willock deserved his luck.

Eintracht are still adapting to the departure of strikers Luka Jovic, Sébastien Haller and Ante Rebic, who scored 56 goals last season. They left Arsenal halfway down, left-back Filip Kostic, who works for Emiliano Martínez and forces a timely block from Xhaka. André Silva later forced another stop at the Arsenal keeper, but the home team had paid for their openness at the other end.

Neither team resumed with the obvious intention of tightening. Within four minutes of the restart, Silva and Bas Dost had missed half chances. within 11 minutes, Aubameyang had been dismissed by Martin Hinteregger's duel at the last moment, after Willock had carried the ball from the deep and Xhaka had hit a free-kick against the crossbar from the right.

Nobody thought to turn off the faucets yet, and Silva should have compensated when she was found out after yet another suggestion from the impressive Kostic.

The pace was relentless, the mistakes almost too big to be counted, and Arsenal kept repeating the blows of concord. A miraculous first touch from Saka gave way to another ball to Willock, whose angled attempt was blocked by Trapp. Willock, whose overall performance was excellent, was soon replaced by Dani Ceballos.

Meanwhile, home support, boosted by the ever-increasing prospect of watching the game behind, had raised the volume. This was reflected in her increasing frustration over the frequent loose passes of Eintracht. It showed in a howl of fear as Dominik, the already booked midfielder Kohr, was sent off after a foul on Saka.

Four minutes before the end, Saka found space outside the box, took aim and bent a precise attempt into the far corner. Within 120 seconds he had played through Aubameyang and was routinely third. What kind of talent is he? What a confusing, crazy and totally convincing team Arsenal is still.