In wet, blustery conditions, Van Poppel pulled ahead of the pack just before the finishing tape to take the 225km stage in 6hr 29min 28sec.
Switzerland's Alex Zulle remains overall leader, still 65sec ahead of his fellow countryman Toni Rominger.
A crosswind sweeping the plains between Aranjuez and Albacete bothered the pack for much of the stage, hampering their rhythm and pace.
The Dutchman, Erwin Nijboer, escaped 43km into the stage and led for more than 150km, at one stage with a lead of 14min. But he was reeled in and disappeared into the pack.Reuse content