Unai Emery has enjoyed a busy summer adding William Saliba, Dani Ceballos and Gabriel Martinelli as well as sealing a club-record deal for Nicolas Pepe from Lille.
But he's not stopping there and is expected to be busy right until the window shuts.
A new defender is high on his wishlist with Luiz emerging as a surprise contender after Laurent Koscielny left the club for Bordeaux on Tuesday.
The Brazilian is interested in reuniting with Emery, who he worked with at PSG, and is understood to have skipped training on Wednesday to try and engineer a move.
Luiz signed a new two-year contract in May, with Chelsea straying from their standard practice of handing one-year extensions to players aged 30 or older.
But it is expected that the Gunners will push to lure Luiz away from Stamford Bridge before the transfer window shuts at 5pm on Thursday with the Blues said to be open to selling him.
Celtic's Kieran Tierney remains another option as Arsenal ramp up their search for defensive options.
The Scottish champions have remained resolute over the left back and have turned down two offers for him already this summer.
But the Daily Mirror report that the Gunners are confident they can strike a deal before the deadline.
The Hoops are looking for a fee in the region of £25m for the Scottish international with personal terms expected to be a formality.
Arsenal remain interested in Juventus' Daniele Rugani as well.
A two-year loan move was initially suggested but the Evening Standard suggest that the Italian champions would instead want £40m to sell him permanently.
It would represent a cheaper alternative to RB Leipzig's Dayot Upamecano with the Germans not budging on their £70m valuation of the Frenchman.
It remains to be seen whether the Gunners would need to move a player or players on before they could sanction any further moves in.
One man who could leave the Emirates on Thursday is Alex Iwobi.
The arrival of Pepe has made first-team opportunities even harder to come by and the club could cash in.
Everton are interested with the BBC reporting that a £30m initial offer has been lodged.
That opening bid is said to have been turned down but they say a deal could be done at the right price.
The Toffees are expected to return with an improved proposal.
Leeds are poised to win the race for forward Eddie Nketiah according to the Press Association.
Bristol City were interested in Nketiah and had been front runners last month before Emery felt the striker would stay for the season.
But the Gunners have now decided to let him leave, despite impressive pre-season performances, ahead of the deadline.
Leeds director of football Victor Orta has a good relationship with Emery and it is understood to have made a personal pitch to Arsenal for the player.
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