MANCHESTER UNITED have agreed a deal to sell Alejandro Garnacho to Chelsea.The Red Devils have sanctioned an exit for the wantaway winger worth £40million.GettyAlejandro Garnacho is joining Chelsea[/caption]Garnacho, 21, will join the Blues on a reported seven-year contract.MORE TO FOLLOW…THIS IS A DEVELOPING STORY..The Sun is your go to destination for the best football, boxing and MMA news, real-life stories, jaw-dropping pictures and must-see video.Like us on Facebook at https://www.facebook.com/TheSunFootball and follow us from our main Twitter account at @TheSunFootball.