On Sunday, the team announced they had optioned the outfielder to Triple-A Reno.
Tomas, 27, had posted a .293 batting average and a .370 on-base percentage with the Diamondbacks this spring. He is a career .268 hitter in the majors.
Even with outfielder Steven Souza Jr. out for the opening week or two of the season, Tomas was at least presumably behind David Peralta, A.J. Pollock, Jarrod Dyson, Chris Owings and Daniel Descalso on the outfield depth chart.
“We sent him down this morning and we have a very competitive camp here,” Lovullo said.