Atletico Madrid have agreed a deal worth 45 million euros for the transfer of Radamel Falcao and Ruben Micael from Porto.
Liga Sagres champions Porto announced the agreement to the Portuguese stock market on Thursday.
Both transfers are subject to the successful completion of medicals, while the players are yet to agree personal terms with La Liga club Atletico.
The transfer values Colombia striker Falcao, 25, at 40 million euros, with the fee potentially rising to 47 million based on performance-based clauses.
Real Madrid and Chelsea had both been linked with moves for Falcao, who scored 38 goals in all competitions last season as Porto won the Portuguese league championship, Portuguese cup and the Europa League.
The former River Plate forward joined Porto in July 2009 and was contracted to the club until 2015.
Atletico are believed to have financed the deal with the proceeds of the sale of Sergio Aguero to Manchester City and David de Gea to Manchester United.
Falcao s transfer fee falls short of his release clause, but the inclusion of Micael in the deal apparently left both clubs satisfied with the outcome of negotiations.
A three-cap Portugal international, Micael cost Porto three million euros from Nacional in January of 2010.
The 24-year-old failed to secure a regular place in the first team at the Estadio do Dragao.
And the signing of Steven Defour from Standard Liege appeared set to push him further out contention.
