Alan Pardew will assess his options ahead of the televised game.
Versatile defender Mapou Yanga-Mbiwa can play at left back, while 21-year-old Paul Dummett is pushing for his Premier League debut.
Whoever gets the nod will face an unenviable challenge given the pace and ability of Navas, signed from Sevilla in a £15m deal this summer.
United’s other left-back, 20-year-old Massadio Haidara, hasn’t featured during pre-season because of a niggling injury.
Manchester City Fixtures
Monday August 19
20:00 Premier League Manchester City v Newcastle United
Sunday August 25
16:00 Premier League Cardiff City v Manchester City
Saturday August 31
12:45 Premier League Manchester City v Hull City
Saturday September 14
15:00 Premier League Stoke City v Manchester City
Sunday September 22
16:00 Premier League Manchester City v Man Utd
Saturday September 28
15:00 Premier League Aston Villa v Manchester City