The 27-year-old defender has attracted interest from several clubs and, despite the transfer window remaining open in Europe for nearly another full month, could move today.
Arsenal have reportedly agreed a fee of £25m to sign the left-back from Celtic and he is expected to undergo a medical today after travelling to London.
Luiz spent two years at Paris St-Germain where he played under Arsenal manager Unai Emery after joining the French club in 2014 before returning to Stamford Bridge.
The defender was a regular under Maurizio Sarri last term and it appeared he would again play a key role under new boss Frank Lampard.
Ludicrous or an excellent move by Emery?
Chelsea are prevented from signing a replacement as they are now serving a transfer ban that allows players to leave but prevents any incoming deals.
It's quite clear that German defender Shkodran Mustafi is not good enough and has made too many errors, while Rob Holding is now out due to an injury and Calum Chambers has not lived up to expectations yet to be leading the backline for a club like Arsenal.
Match action is more assured in north London given Arsenal's limitations in central defence, which led them to pursue a late deal for Luiz.