Østberg, a one-time event winner in the FIA World Rally Championship, was competing in the ERC under the MRF Tyres Dealer Team banner for the first time.
Despite limited testing before the northern Portuguese event got underway, Østberg took two stage wins and was leading until stage six before he eventually finished in the runner-up spot, just 10.8sec behind winner Hayden Paddon.
Speaking at the finish in Fafe, the 35-year-old, who was co-driven by Swede Patrik Barth, said: “At the end we are happy with the result but I feel very sorry for Mikko [Heikkilä] for his puncture on the last stage. We fight very hard over the whole rally and so did Hayden and so did Mikko so I would have been surprised if all three cars came to the end without any issues.
“For us we were happy to be in the fight because there are some very, very fast drivers in the ERC. Looking back at the weekend we have done the maximum of what we had in us and now and we have to improve. We had a completely new package so we have to learn that package before we are 100 per cent. We know that and we knew it before the rally because we had half a day of testing and that’s it and with a new package like this it’s not enough basically.”
Østberg, who won the WRC2 title in 2020, is undertaking a full ERC campaign this season in a Citroën C3 Rally2 following on from his capture of the Hungarian championship in 2022.