Julian Weigl has joined Benfica from Borussia Dortmund in a €20 million (£17m/$22m) deal.
The 24-year-old defensive midfielder spent four and a half years with the Bundesliga side and had been a regular in Lucien Favre's team this season, making 20 appearances in all competitions.
The Germany international had previously been linked with a move to Paris Saint-Germain, as former Dortmund boss Thomas Tuchel admitted interest in him at the end of last season.
Serie A side Inter had also reportedly been eyeing him as a potential signing as they look to strengthen in midfield, but the Primeira Liga side have swooped in and struck a deal with Dortmund.
"I would like to thank my team-mates, the Dortmund staff and all the fans of this great club for a great time and I will always have Borussia Dortmund at heart," Weigl told Dortmund's website as his move was announced.
— Borussia Dortmund (@BlackYellow) December 31, 2019
"Julian came to us with this wish, and we agreed - also because of his services to the club," sports director Michael Zorc said. "We wish him all the best for his future!"
Weigl, who has represented his national team five times since his 2016 debut, made 171 appearances in all competitions for Dortmund and won the DFB-Pokal and DFL-Supercup in his time at the club.
He leaves a Dortmund side sitting fourth in the Bundesliga table - seven points off leaders RB Leipzig with 17 games played - just days after they completed the first high-profile capture of the window in Red Bull Salzburg sensation Erling Haaland in a deal worth €20m.
Benfica are top of the Primeira Liga and four points clear of second-placed Porto, while they face Ukrainian side Shakhtar Donetsk in the last 32 of the Europa League, having dropped out of the Champions League after finishing third in Group G.