Stoke have broken their transfer record to sign midfielder Giannelli Imbula from Porto for a fee of £18.3m on a five-and-a-half-year contract.
The 23-year-old became Portuguese football's record signing when he joined Porto in a £15.1m deal from Marseille seven months ago.
He has played for France Under-21s, but could also play for Belgium.
The Potters have let Chelsea midfielder Marco van Ginkel leave his loan spell early to join Dutch club PSV.
The 23-year-old, capped twice by the Netherlands, had played 21 times for Stoke during a season-long loan spell, but he will now be in Eindhoven until the summer.
Stoke's previous record deal was winger Xherdan Shaqiri, who cost £12m in the summer.
Imbula, who started his career at Guingamp, played in both of Porto's Champions League games against Chelsea this season.
Potters chairman Peter Coates told BBC Radio 5 live: "If he is as good as we think he is, he'll keep his value. You've got to think of it from a business point of view. We want him to be worth more than we paid for him.
"This move has been on and off for a few days. We said we were withdrawing the offer, then they came back."
Stoke midfielder Charlie Adam told BBC Sport: "We played Porto in a friendly in Germany last summer and I thought he was excellent.
"He went off injured because I gave him a little kick and gave him a dead leg, but he showed against us that he has the right qualities to play in England.
"I would say he is a Patrick Vieira type - a strong and powerful midfielder, a real driving force in there and perfect for the Premier League."
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