First, gunners need to be excellent at protecting the set pieces.
They weren’t at their best against Bournemouth, but they were in control of the game as visitors were not managing their shots on the target for the first hour.
But their first such attempts resulted in an equalizer when Dean Huissen came out of Antoine Semenro’s long throw.
The set piece was for Arsenal to undo for the winner as the corner flicked to the far post for Evanilson to bundle.
Of the targets Arsenal has recognized this season, 38.7% comes from set-piece situations – the most on the UK’s top flights.
Arsenal will have to score on Wednesday and somehow have to lock out the PSG side, which scored a league-high 42 goals in 16 league-1 games at home this season.
In the last five Premier League matches, Arsenal led, but in those four games they couldn’t retain that advantage.
In total, they dropped 21 points from their winning position in the Premier League this season.
Another concern arising from Saturday’s defeat was that gunners did not manage one attempt on or off the target after Bournemouth took the lead in the 75th minute.
“At that moment you can’t see it [Arsenal beating PSG]”Former West Ham goalkeeper Rob Greene spoke on BBC Radio 5 Live.
“You have a group of players despite your confidence and ideas about how to take Declan Rice from this team equation, get goals and have a sharp edge.
“There’s work to do and there’s very little time to do it.”
