Arsenal were thoroughly outplayed but only beaten by a single Ousmane Dembele goal in the first leg of their Champions League semi-final against Paris Saint-Germain.
Overcoming a one-goal deficit isn't beyond Arsenal in Paris in eight days, but Mikel Arteta will need a lot more from key players. Specifically, Martin Odegaard, who went missing in a game where he simply didn't see enough of the ball.
Then there was Gabriel Martinelli, who endured a calamitous evening as a liability in attack. Martinelli also faltered as part of an inconsistent press that didn't put enough pressure on PSG in midfield.
Smart, slick and swift passing through all three phases engineered Dembele's goal in the fourth minute. Mikel Merino thought he'd headed in an equaliser from the familiar route of a set-piece mere minutes after the restart.
Arsenal will rue the judgement of VAR, although the tight offside call was just about correct. Frankly, the Gunners ought to be relieved they didn't concede more because the visitors wasted two glorious chances to pad their lead during the late stages.
Those let-offs mean the dream isn't over yet, but Arteta has a lot of work to do to refresh the formula before the second leg.
Positvies & negatives from Arsenal 0-1 PSG in first leg of semi-final

Negative #1: Misfiring Martinelli
It would be an understatement to say this was far from Martinelli's best game. The Brazilian was closer to an outright disaster-class than to merely suffering an off night.
Some loose touches married with a shoddy appreciation of the offisde rule to conspire to make Martinelli a liability for most of the first half. When the wide forward did find some rare space, he failed to use it effectively.
In fairness, those failures weren't all down to Martinelli-made deficiencies. He also found himself denied by a strong stop from PSG's towering goalkeeper Gianluigi Donnarumma, who unfortunately chose the big occasion to enjoy a special night.
Donnarumma's defiant brilliance aside, Arsenal needed more from Martinelli. More straight-line pace on the break, more clever turns and a more intelligent application of space.
Unfortunately, Martinelli couldn't answer the call. Instead, this kind of lacklustre effort under the unforgiving spotlight of a showpiece tournament served as a reminder the 23-year-old is still some ways off making that vital step from potential to stardom.
It's the same step Martinelli's fellow winger has had little trouble making.
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