Southampton have signed 20-year-old midfielder Mateus Fernandes from Sporting Lisbon for around £15 million on a five-year deal. Fernandes, who has represented Portugal at various youth levels and spent last season on loan at Estoril, described joining the Premier League as a 'dream come true.' Southampton manager Russell Martin expressed excitement about Fernandes's potential impact, highlighting his energy, possession skills, and forward-thinking play. Fernandes is the 11th addition to Southampton's squad this summer and is expected to compete for a starting spot. The midfielder has made a few appearances for Sporting this season and has been capped seven times by Portugal's U21 side.