Isotropy of virtual Albert forms over function fields of quadrics

Let F be a field of characteristic different from 2 and let phi be a virtua l Albert form over F, i.e., an anisotropic 6-dimensional quadratic form ove r F which is still anisotropic over the field F(rootd+/-f). We give a compl ete description of the quadratic forms y such that phi becomes isotropic ov er the function field F(psi). This completes the series of works ([H6], [La g6], [Lag], [Lee], [M2]) where the question was considered previously.