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Subduction infancy is recorded by upper plate magmatism and lower plate metamorphism, i.e., supra-subduction zone (SSZ) ophiolite-metamorphic sole pair. Here, we report geochemical and geochronological data as well as P-T calculations of amphibolites (metamorphic sole) and hornblende gabbros (SSZ ophiolite) from the Saga ophiolitic mélange in Tibetan Plateau. Amphibolites show trace element contents compatible with normal-mid-ocean ridge basalt (N-MORB), indicating that the protoliths formed in a MOR setting. Instead, hornblende gabbros show significant high field strength elements (HFSEs) negative anomalies, enriched large ion lithophile elements (LILEs) and high zircon εHf(t) values, suggesting they formed by fluid-induced partial melting of a depleted mantle. Thermobarometers and phase equilibrium modelling suggest two stages of metamorphism for garnet-clinopyroxene amphibolites: (I) a peak metamorphic stage (~1.9 GPa/1030 °C) and (II) a retrograde metamorphic stage (1.1-1.6 GPa/800-1000 °C). Zircon U-Pb ages of amphibolite and hornblende gabbro are 128.84±5.07 Ma and 128.12±1.52 Ma, respectively, suggesting roughly coeval formation of the metamorphic sole and SSZ ophiolite and inception of a subduction zone within the eastern Neo-Tethys prior to 128 Ma. Apatite U-Pb ages of amphibolite and hornblende gabbro are 121.8±2.1 Ma and 117.5±4.5 Ma, respectively. Titanite U-Pb age of amphibolite is 122.2±1.5 Ma. Overall, our data suggest that the metamorphic sole was rapidly exhumed shortly after its formation whereas the hornblende gabbro stagnated between 128-118 Ma, and was then exhumed into the ophiolitic mélange.