Everton have agreed to sign Barcelona's Colombia centre back Yerry Mina for an initial 30.25 million euros and have also taken the club's midfielder Andre Gomes on loan, the Spanish champions said on Thursday.
The fee could rise by 1.5 million euros and Barcelona have inserted a buy-back clause in the player's contract.
At worldwide level, he was also part of the Brazil team who won the 2013 FIFA Confederations Cup and played for his country at their home World Cup in 2014.
Allardyce, who was in charge of the club last season, believes that his former employers may have an issue with unhappy players at Goodison Park this season. This is a great opportunity for me and I am looking forward to competing here.
"Barcelona would like to publicly express their thanks to Yerry Mina for his commitment and dedication and wishes him all the best for the future".
Mina only joined Barca in January from Brazilian side Palmeiras.
Everton had been willing to listen to offers for Congolese worldwide Bolasie, while Martina has been training with the reserves as he looks to force a £2m move away from Goodison Park. Bernard wanted £200,000 a week earlier in the summer but the 25-year-old ultimately lowered demands that had deterred interest from West Ham, Chelsea and Milan, among others.
The Portugal worldwide joined Barcelona from Valencia for an initial €35m two years ago but has struggled to make an impact at the club. He joins Lucas Digne at Everton, a player who arrived at Barcelona at the same time he did, with similar levels of success. He has made just six appearances during his time in Spain.