Blood clotting, a process to avoid bleeding, involves vasoconstriction, platelet plug build-up, coagulation, clot retraction and fibrinolysis. During coagulation, blood changes from liquid to gel, and the clot viscoelastic properties continue modifying until fibrinolysis. Tests to analyze bleeding disorders and anticoagulant therapy include clot-based assays, to detect the end-point of fibrin network in a plasma sample, and viscoelastic methods to trace the kinetics of whole blood coagulation. Ultrasound (US) methods are reported to measure clotting times, similar to clot-based assay findings, and shear modulus, μ, and viscosity, η, of the formed clot. This work objective was to measure μ, during plasma clotting, based on the vibration signature induced by impulsive acoustic radiation force (iARF) on an embedded sphere.