Due to travel restrictions due to COVID-19, this match took place in Rome though the Portuguese side were the designated hosts.
Arsenal captain Pierre-Emerick Aubameyang should have given Arsenal the lead in a first half which finished goalless as he inexplicably shot wide when presented with a golden chance from close range.
Mikel Arteta’s side looked like they could be made to pay for that miss when Benfica took the lead on 55 minutes after Pizzi converted a penalty awarded due to a handball from Arsenal’s Emile Smith-Rowe.
But the visitors were level within two minutes as Saka converted from close range following a great ball from Cedric Soares.
The return leg, in with Arsenal will be the home team, will take place in Athens on March 4.