Nottingham Forest have signed Benfica's Joao Carvalho for a club-record fee of £13.2m and completed a season-long loan deal for team-mate Diogo Goncalves.
Midfielder Carvalho, 21, played eight games for Benfica in 2017-18 and has signed a five-year contract.
Forest's deal for winger Goncalves, also 21, includes an option to buy at the end of his loan spell.
The Portugal Under-21 pair have joined the Championship club after passing medicals on Thursday.
The deal for Carvalho eclipses Forest's previous record transfer fee, which was for striker Britt Assombalonga, who joined from Peterborough for £5.5m in August 2014.
The Reds sold him to Middlesbrough for £15m in July 2017.
Colin Fray, BBC Radio Nottingham's Forest correspondent
If you are spending the sort of money Forest are spending, you would expect quality from the players you are bringing in as a given - so let's assume that will be the case.
For me the important thing about these signings is the message it sends out. It answers a question fans have been asking since Evangelos Marinakis took over: 'How much money is he prepared to spend to really have a go at bankrolling Forest into the Premier League?'
A deal this size at Championship level would suggest he is very serious about getting Forest into the top flight. He is also serious, maybe, about doing it this season. Forest are not prepared, it seems, to have another season of consolidation.
Instead they are prepared to have a right go, spending the kind of money that Wolves did last season - we all saw the benefits and they will be playing in the Premier League next season.
Can Forest emulate Wolves?
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