Blackmar Diemer Gambit Declined Okelly Defense Advanced (1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 c6) in Chess

The Blackmar Diemer Gambit Declined Okelly Defense Advanced is an advanced sideline of the Blackmar–Diemer Gambit where Black declines the gambit and steers into the O’Kelly-style setup. In this “advanced” version, the defining feature is that Black’s pieces are developed to meet White’s central and queenside pressure without accepting the pawn sacrifice, typically after the Blackmar–Diemer’s early pawn thrusts and White’s follow-up pressure. I don’t have a reliably documented, universally agreed exact move order for the “Advanced” label in this specific O’Kelly-declined branch, so treat the c