Santi Cazorla is expected to return from injury this week, joining Mikel Arteta, Mathieu Flamini, Tomas Rosicky, Alex Oxlande-Chamberlain, Jack Wilshere, Mesut Ozil and Aaron Ramsey in the competition for places at the Emirates Stadium.
Parlour reserved special praise for Ramsey, who has scored five goals already this season.
"When you look at teams like Barcelona, their midfield has always been the most important part of their game so hopefully Arsenal will be very similar," Parlour told the club's official website.
"It's looking very strong, no matter who starts, there is so much depth in the midfield. It's a real headache for the manager.
"Aaron Ramsey's been the player of the season so far, he's been superb with the goals he's scored but the whole midfield are very adaptive now."
The former England international, 40, won three Premier League titles, four FA Cups, a League Cup and a Cup Winners' Cup medal during his 12 years with the club.