The Australian was defeated by world No.9 Ferrer 6-4 3-6 6-1 at the hardcourt tournament on Friday.
Tomic has been in solid if not spectacular form over the past month since his exit at the round-of-16 stage of the Australian Open, reaching the quarters at the Memphis Open and the semi-finals at Delray Beach in Florida last week.
Ferrer will now face Ryan Harrison in the semis after the American upset big-serving Croatian Ivo Karlovic, following on from his victory over defending champion and world No.10 Grigor Dimitrov in the second round.
The other semi pits top seed Kei Nishikori against towering South African Kevin Anderson.
