Subsoil compaction is a major constraint to soil functioning worldwide, limiting crop productivity and reducing the capacity of agroecosystems to efficiently use water and mitigate greenhouse gas emissions. This study evaluated the medium to long-term effects of cover crops, mechanical decompaction using a paraplow, and their combination on soil physical and hydraulic properties, and on crop performance in four sites cultivated with no-till under semi-arid conditions. Field experiments were conducted over three to four years at four sites in the central Argentinean Pampa (three Petrocalcic Paleustolls and one Typic Haplustoll). Treatments included mechanical decompaction with cover crops, cover crops alone, mechanical decompaction alone, and an untreated control. Cover crops were oat (Avena sativa), triticale (& times;Triticosecale Wittmack), or rye (Secale cereale), depending on site. Bulk density, maximum bulk density, critical moisture, and susceptibility to compaction were determined at the start of the experiment (0-0.20 m). Infiltration rate and hydraulic conductivity (0-0.24 m) were measured periodically throughout the study. Crop yield, root biomass, and water use efficiency were quantified for both cover and cash crops. Mechanical decompaction increased infiltration rate by 7-8 times relative to the control immediately after treatment, but this effect declined over time. In contrast, treatments including cover crops maintained higher infiltration rates and showed greater and more persistent improvements in hydraulic conductivity. These effects varied among sites according to soil texture and initial compaction status. Cover crops, alone or combined with mechanical decompaction, increased crop yield, root biomass, and water use efficiency for at least three growing seasons. Strong relationships were observed between root biomass and both crop yield and water use efficiency, particularly in treatments including cover crops. The results demonstrate that integrated approaches combining mechanical decompaction and cover crops provide an effective strategy for the long-term regeneration of compacted soils, enhancing soil hydraulic functioning and crop productivity in semiarid environments.