Sclerotinia sclerotiorum (Lib.) de Bary, the causal agent of stem rot in Indian mustard (Brassica juncea) and other oilseed Brassicas, is a cosmopolitan necrotrophic pathogen capable of inflicting yield losses of up to 80% in severely affected fields (Rai et al., 2024). Conventional management relying on partial host resistance, cultural practices, and systemic fungicides has proven inconsistent and environmentally costly, prompting interest in mycovirus-mediated hypovirulence as an alternative biological control strategy. This review synthesizes two decades of research on hypovirulence-inducing mycoviruses infecting S. sclerotiorum, with particular emphasis on the single-stranded DNA virus Sclerotinia sclerotiorum hypovirulence-associated DNA virus 1 (SsHADV-1) and co-infecting RNA mycoviruses such as endornaviruses and hypoviruses. Evidence from laboratory, greenhouse and field studies demonstrates that these agents attenuate fungal growth, sclerotial development, and virulence-factor expression through RNA-silencing suppression, disruption of G-protein-coupled signal transduction, and transcriptional reprogramming of pathogenicity genes, in some cases converting the pathogen into a beneficial endophyte that promotes plant growth and induces systemic resistance. Unlike most mycoviruses, SsHADV-1 is unusual in being infectious extracellularly, allowing it to bypass the vegetative-incompatibility barriers that have historically constrained biocontrol efforts built around hypoviruses such as CHV-1 in Cryphonectria parasitica. Despite these advances, translation to mustard fields remains constrained by formulation instability, incomplete understanding of natural transmission routes, and the near-total absence of dedicated studies in Brassica juncea rather than B. napus. This review critically evaluates the mechanistic basis and comparative advantages and limitations of virocontrol relative to conventional approaches and proposes priority research directions, including vector-mediated transmission, seed bio-priming, and mycovirus prospecting in Indian isolates to accelerate deployment of hypovirulence-based management in mustard-growing regions.