Goals from captain Katie McCabe, Leanne Kiernan and Louise Quinn secured the victory against the hosts, who qualified for the European Championships in the summer, with Diana Silva’s strike a late reply.
Ireland suffered a narrow 1-0 defeat in the first international friendly between the two sides on Thursday and Head Coach Colin Bell made two changes from the defeat. Ruesha Littlejohn started her first game since September 2016 and she was partnered up front by Shelbourne striker Leanne Kiernan.
The latter was heavily involved for Ireland’s opener just past the half-hour. Peamount winger Heather Payne latched onto a loose ball on the half-way line and put Kiernan through down the right, and it was her brilliant cross which found McCabe to head home.
Three minutes after the break, Kiernan had a deserved goal of her own. Niamh Fahey played a long ball forward and the Cavan-native used her blistering pace to beat the defender to the ball and fire home over the keeper.
Ireland continued to dominate the game with a McCabe long-range effort just tipped over in the 50th minute before Arsenal defender Quinn added a third and secured the victory.
The quick-thinking McCabe collected a short left-sided corner and found a pin-point cross for Quinn to rise highest and head home off the post. Diana Silva scored a consulation for the hosts with 10 minutes remaining as Ireland get the perfect result to round off the two-game week in the Azores.
Republic of Ireland WNT Head Coach Colin Bell said: “It was a deserved victory. We were much better today. I thought we were very sluggish on Thursday, maybe the long journey had an effect but that was much improved.
“We made a couple of changes and put two up front, and I think we created plenty of problems for Portugal. They’re a very good side but as soon as we scored the first goal, we were in control of the game and got the result.
“They were fantastic goals and I’m delighted for Leanne Kiernan who performed to the levels we know she’s capable of today. She’s trained really well over the past two days and got a deserved goal, I’m delighted for her.
“They were plenty of great performances and it’s been another important week as we continue to prepare for the qualifiers in April. This is a great result to keep that momentum going and we can take plenty of confidence from this.”
Republic of Ireland: Hourihan (GK), Payne, Caldwell, Quinn, Fahey, Scott, Toland, O'Sullivan, McCabe (C), Littlejohn (McLoughlin 81), Kiernan (Atkinson 90).