Afterwards he served under Michael VII Doukas (1071–78) and Nikephoros III Botaneiates (1078–81) in various responsible positions on both the eastern and the western frontiers of the empire. Later Gregory was involved in a coup that removed Nikephoros III. The new Emperor, Alexios I Komnenos, appointed him ""megas domestikos" of All the West" and gave him many more properties in the Balkans. He possessed numerous estates in various parts of the Byzantine Empire and was afforded a variety of privileges by the emperor, including exemption from certain taxes. In 1081, he commanded the left flank against the Normans at the Battle of Dyrrachium. A year later he evicted the Normans from Moglena. He died in 1086 fighting the Pechenegs at the battle of Beliatoba, charging so vigorously he crashed into a tree.