In 1998, Gilkey was traded to the Arizona Diamondbacks. Gilkey's offensive numbers were less impressive in the latter years of his career and his playing time declined, although he did rebound to hit .294 in 1999.
In 1998, Gilkey was moved to the Arizona Diamondbacks. His offensive performance declined during the latter stages of his career, leading to a decrease in playing time. However, he managed to regain some form and hit .294 in 1999.