With five wins in the six events prior in their Team Aicello Skoda Fabia, Kovalainen and his co-driver Sae Kitagawa went into last weekend's Rally Hokkaido almost guaranteed of the crown in their first year of competing in the JRC's top JN-1 class for four-wheel drive cars.
Despite finishing only ninth while his nearest title rival Norihiko Katsuta won the rally, Kovalainen was handed the crown by default as it transpired that next month's final round of the season, Rally Highland Masters, will not offer enough points to allow the Finnish driver to be caught.
It marks Kovalainen's second title success in the JRC following his triumph in the JN-2 class in a two-wheel drive Toyota 86 last year.
Kovalainen endured a difficult weekend in Hokkaido, only the second event of the season to be held on gravel, as he suffered an off on Saturday's fifth stage that cost him 22 minutes.
"I couldn't change the punctured tyre very well because of some damage to the jack mount, so I had to improvise and find another solution to lift the rear of the car up and eventually get it changed," Kovalainen said.
"But I knew coming into the weekend that we had already won the championship, so I went a bit harder and it didn't work out well!"
After the Rally Highland Masters season finale next month, Kovalainen will turn his focus to his planned one-off appearance in the WRC on the championship's return to Japan in November.
The 2016 Super GT champion says he is looking forward to returning to tarmac for both of those events, having proven to be the class of the field in the JRC on sealed-surface roads this year.
"This weekend in Hokkaido has shown I've got a lot to learn on gravel," he admitted. "I feel I'm not driving well on these high-speed, slippery roads, so that's an area that I will have to practice a lot in future if I want to make progress.
"I'm more confident on tarmac, so I'm looking forward to the final round of the JRC and the WRC even if this one didn't work out. That said, I want to increase my speed and these things happen in the process! It's a part of the game."
Kovalainen has yet to decide on his plans for 2023 but previously indicated to Autosport he will prioritise his rallying exploits over any potential return to circuit racing, following his retirement from SUPER GT last year.