Ghana defender Daniel Opare was among 31 players unveiled by Portuguese giants FC Porto for the 2014/2015 season and handed the number 44 jersey.
The versatile defender has been battling for fitness after joining them from the 2014 World Cup finals.
He joined the former European champions as a free agent after ending his contract with Belgian side Standard Liege.
Opare and goalkeeper Helton and new signing Defour have been working out in the gym to step up their fitness level for the start of the season.
The 23-year-old missed the pre-season friendly against Saint-Etienne at the Estadio do Dragao on Sunday which ended 0-0.
Porto's squad for 2014/2015 season:
1 - Helton, 2 - Danilo, 3 - Martins Indi, 4 - Maicon, 6 - Casemiro, 7 - Quaresma, 8 - Brahimi, 9 - Jackson Martínez;
10 - Quintero, 11 - Tello, 12 - Fabiano, 13 - Reyes, 15 - Evandro, 16 - Herrera, 18 - Adrián López, 19 - Sami, 20 - Carlos Eduardo, 21 - Ricardo, 24 - Ricardo Nunes,
26 - Alex Sandro, 28 - Kelvin, 30 - Óliver Torres, 35 - Defour, 36 - Rúben Neves, 39 - Gonçalo Paciência, 41 - Kadú, 43 - Igor Lichnovsky,
44 - Opare, 50 - Graça, 52 - Víctor García and 77 - Joris Kayembe.