Tuyere stock arrangement (10) of a blast furnace comprising a tuyere body (20) configured for installation in a shaft furnace wall (12), the tuyere body (20) comprising a front face (24) facing an interior of the shaft furnace and an opposite rear face (26), a tuyere channel (28) extending from the rear face (26) to the front face (24). The tuyere stock arrangement (10) further comprises a blowpipe (34) connected between the rear face (26) of the tuyere body (20) and a hot blast air supply system (38, 39), the blowpipe (24) having a front portion (32) connecting to the tuyere body (20) and an opposite rear portion (36) connecting to the hot blast air supply system (38, 39). A fuel injection lance (40, 40') is provided for feeding fuel into the shaft furnace and a gas injection lance (44, 44') is provided for feeding an oxidizing gas to the shaft furnace, the fuel injection lance (40, 40') being arranged through the tuyere body (20). According to an important aspect of the invention, the gas injection lance (44, 44') is arranged in the rear portion (36) of the blowpipe (34), the gas injection lance (44, 44') being arranged in such a way as to feed the oxidizing gas into a central portion of a stream of hot blast air fed through the blowpipe (34).