Ireland's women regrouped from Tuesday's 7-0 hammering by Spain to defeat the hosts 2-0 in the Costa del Sol resort of Benalmadena on Thursday.
Katie Mullan put Ireland ahead on 29 minutes with Lena Tice adding the second from a penalty stroke as the Irish bossed the second half.
Grace O'Flanagan did have to make a number of fine late saves to prevent a Spanish response.
The series continues with further games on Saturday and Sunday.
Ireland coach Graham Shaw was delighted with the response of his players after Tuesday's disappointing performance.
"We played a lot quicker today, at international pace, which allowed us to play out the game," said Shaw.
"We now need to build on that platform for Saturday and Sunday's fixtures."