The reigning world champion was expecting a tall order in Sardinia starting first on the gravel stages on Friday at a rally that has yielded a best result of fifth in three previous top-tier attempts.
However, the Finn finished third behind Hyundai duo Thierry Neuville and Esapekka Lappi after coming through desperately tricky conditions on Friday morning, before rain showers added to the challenge across the remainder of the weekend.
The 22-year-old enjoyed a relatively trouble-free run through the 19 stages, although he did suffer a scare on Friday when he had to take evasive action after encountering a small herd of cows during the first pass through the 49.9km Monte Lerno stage.
Rovanpera added an extra five points to his haul by winning the rally-ending and rain-impacted Power Stage by a margin of 4.7s over M-Sport's Ott Tanak.
"I didn't think we would be getting 20 points when I came here but yeah, the plan was to try to be fast and steady the whole weekend," Rovanpera told Motorsport.com.
"We knew we had the pace when needed and we were clever when we needed to be, so I think it was a really clever drive from our side.
"This has always been a tricky event for me personally. We had quite good pace overall and stayed out of trouble and at the start of the weekend I really didn't expect that we could end it with this many points."
When asked about his Power Stage win he added: "It was a good plan, to be honest, and after yesterday we tried to focus on the Power Stage.
"There were still some cars with good tyres like us and it was a good run through so happy with the points."
Rovanpera's points haul has extended his championship lead to 25 points over Neuville, who has climbed into second spot following his victory on Sunday.
The championship heads to Africa for Safari Rally Kenya (22-25 June) which was where he scored one of six wins on his way to a record-breaking 2022 world title.