A multi-phase hot-rolled steel sheet characterized by: having a chemical composition comprising, in mass percent, C: at least 0.07% and at most 0.2%, Si + Al: at least 0.3% and at most 1.5%, Mn: at least 1.0% and at most 3.0%, P: at most 0.02% S: at most 0.005%, Cr: at least 0.1% and at most 0.5%, N: at least 0.001% and at most 0.008%, one or two of Ti: at least 0.002% and at most 0.05% and Nb: at least 0.002% and at most 0.05%, optionally one or more of V: at most 0.2%, Cu: at most 0.2%, Ni: at most 0.2%, and Mo: at most 0.5%, and a remainder of Fe and impurities, having ferrite with an area fraction at least 7% and at most 35%, the ferrite having a grain diameter of at least 0.5 μm and at most 3.0 μm and a nanohardness of at least 3.5 GPa and at most 4.5 GPa, and having a second phase which is the remainder other than ferrite, the second phase including martensite and at least one selected from bainitic ferrite and bainite and having an average nanohardness of at least 5 GPa and at most 12 GPa, the second phase containing a high-hardness phase of at least 8 GPa and at most 12 GPa primarily comprising martensite with an area fraction of at least 5% and at most 35% with respect to the overall structure, wherein the area fraction of the bainitic ferrite and/or the bainite with respect to the second phase as a whole is greater than 50%. having a chemical composition comprising, in mass percent, C: at least 0.07% and at most 0.2%, Si + Al: at least 0.3% and at most 1.5%, Mn: at least 1.0% and at most 3.0%, P: at most 0.02% S: at most 0.005%, Cr: at least 0.1% and at most 0.5%, N: at least 0.001% and at most 0.008%, one or two of Ti: at least 0.002% and at most 0.05% and Nb: at least 0.002% and at most 0.05%, optionally one or more of V: at most 0.2%, Cu: at most 0.2%, Ni: at most 0.2%, and Mo: at most 0.5%, and a remainder of Fe and impurities, having ferrite with an area fraction at least 7% and at most 35%, the ferrite having a grain diameter of at least 0.5 μm and at most 3.0 μm and a nanohardness of at least 3.5 GPa and at most 4.5 GPa, and having a second phase which is the remainder other than ferrite, the second phase including martensite and at least one selected from bainitic ferrite and bainite and having an average nanohardness of at least 5 GPa and at most 12 GPa, the second phase containing a high-hardness phase of at least 8 GPa and at most 12 GPa primarily comprising martensite with an area fraction of at least 5% and at most 35% with respect to the overall structure, C: at least 0.07% and at most 0.2%, Si + Al: at least 0.3% and at most 1.5%, Mn: at least 1.0% and at most 3.0%, P: at most 0.02% S: at most 0.005%, Cr: at least 0.1% and at most 0.5%, N: at least 0.001% and at most 0.008%, one or two of Ti: at least 0.002% and at most 0.05% and Nb: at least 0.002% and at most 0.05%, optionally one or more of V: at most 0.2%, Cu: at most 0.2%, Ni: at most 0.2%, and Mo: at most 0.5%, and a remainder of Fe and impurities, having ferrite with an area fraction at least 7% and at most 35%, the ferrite having a grain diameter of at least 0.5 μm and at most 3.0 μm and a nanohardness of at least 3.5 GPa and at most 4.5 GPa, and having a second phase which is the remainder other than ferrite, the second phase including martensite and at least one selected from bainitic ferrite and bainite and having an average nanohardness of at least 5 GPa and at most 12 GPa, the second phase containing a high-hardness phase of at least 8 GPa and at most 12 GPa primarily comprising martensite with an area fraction of at least 5% and at most 35% with respect to the overall structure, wherein the area fraction of the bainitic ferrite and/or the bainite with respect to the second phase as a whole is greater than 50%.