That is according to Arsenal legend and BT Sport pundit Martin Keown.
The Gunners beat Valencia 3-1 at the Emirates thanks to two goals from Alexandre Lacazette and a late strike by Pierre-Emerick Aubameyang.
Aubameyang’s goal makes Arsenal big favourites to make the final to face either Chelsea or Eintracht Frankfurt, who drew 1-1 in their first leg.
Head coach Unai Emery made all three substitutions in the second half, with Lucas Torreira, Henrikh Mkhitaryan and Mesut Ozil all coming on.
The trio replaced Matteo Guendouzi, Mesut Ozil and Laurent Koscielny, with the latter appearing to be suffering with an injury.
Keown believed Arsenal saw out the game well and believes that eleven players his what Emery should field in the return leg in Spain.
“That third goal is so important,” Keown said.
“Valencia, in fairness, I thought they were trying to settle for 2-1 and it’s backfired on them big time.