Esapekka Lappi has been confirmed as Sebastien Ogier's team-mate at Citroen for the 2019 World Rally Championship season.
Lappi contested eight of last year's 13 WRC rounds for Toyota, earning a deal to complete the season on the back of an impressive performance on Rally Italy, and secured a full-season drive with the manufacturer for 2018.
He is currently fourth in the points with three podium finishes.
Lappi was first linked to a move to Citroen for 2019 last month, and has now completed a deal to join Citroen - where he hopes to further his WRC education alongside five-time champion Ogier.
"Obviously, I'm delighted to be joining the team and to be the future team-mate of Sebastien," said Lappi.
"It's a good opportunity for me to keep developing.
"Having learned many things from [Toyota team-mates] Jari-Matti Latvala last year, and from Ott Tanak this year, I'll have everything it takes to be even better if I also manage to draw inspiration from Seb."
Lappi admitted Citroen team principal Pierre Budar's enthusiasm to draft him in was one of the reasons he decided to depart the Toyota outfit, which announced Kris Meeke in its line-up for 2019 on Wednesday morning.
"I'm convinced that the car has a lot of potential, as does the team, which has a long history and lot of experience in the WRC," added Lappi.
"The fact that Pierre clearly wanted to recruit me also counted a lot when it came to making my decision."
Budar said capturing Lappi furthered Citroen's policy of bringing young drivers forward, but added he felt the Finn - who won Rally Finland last year - still has room for development.
"We were keen to sign up two very competitive crews for next year and the arrival of Esapekka is, therefore, excellent news," said Budar.
"Putting faith in young drivers has long been hard-wired in the DNA of our brand and Esapekka certainly has the ideal profile.
"Talented, determined and focused, he should form both a complementary - and formidable - pair with Sebastien.
"We feel there is still more to come from him, so we'll be doing what we can to get him in the best possible shape to help him continue his impressive rise through the ranks."
Citroen is thought to be likely to contest most WRC rounds with just two C3s next season, with a third car potentially run for Sebastien Loeb or Khalid Al Qassimi.
It is not known what Lappi's arrival means for current Citroen drivers Craig Breen and Mads Ostberg, but Breen's name has increasingly been linked to a full-time 2019 programme at M-Sport.