Previous experimental and theoretical work has established that electronic excitation of a guanine cation radical in nucleosides or in DNA itself leads to sugar radical formation by deprotonation from the dexoxyribose sugar. In this work, we investigate a ground electronic state pathway for Such Sugar radical formation in a hydrated one electron oxidized 2'-deoxyguanosine (dG(center dot+) + 7H(2)O), using density functional theory (DFT) with the B3LYP functional and the 6-3IG* basis set. We follow the stretching of the C-5'-H bond in dG(center dot+) to gain an understanding of the energy requirements to transfer the hole from the base to sugar ring and then to deprotonate to proton acceptor sites in solution and oil the guanine ring. The geometries of reactant (dG(center dot+) + 7H(2)O), transition state (TS) for deprotonation of the C-5', site, and product (dG(C-center dot(5'), N-7-H+) + 7H(2)O) were fully optimized. The zero point energy (ZPE) corrected activation energy (TS) for the proton transfer (PT) from C-5' is calculated to be 9.0 kcal/mol and is achieved by stretching the C.(5')-H bond by 0.13 angstrom from its equilibrium bond distance (1.099 angstrom). Remarkably, this small bond stretch is sufficient to transfer the "hole" (positive charge and spin) from guanine to the C-5' site on the deoxyribose group. Beyond the TS, the proton (H+) spontaneously adds to water to form a hydronium ion (H3O+) as all intermediate. The proton Subsequently transfers to the N-7 site of the guanine (product). The 9 kcal/mol barrier suggests slow thermal conversion of the cation radical to the sugar radical but also suggests that localized vibrational excitations would be sufficient to induce rapid Sugar radical formation in DNA base cation radicals.