Manchester United legends and fans have flooded the comments section of Rio Ferdinand's Instagram post announcing his son's first professional contract. Lorenz, who plays as a goalkeeper, has penned a deal at Brighton & Hove Albion after impressing last season.The 18-year-old made his Premier League 2 debut in January of this year, before going on to make his senior debut for Havant and Waterlooville, a seventh-tier side in England, in April. He managed to keep two clean sheets in his six matches on his 'work experience loan' with the Southern League side. View this post on Instagram Instagram PostThe teenager played 20 matches for Brighton & Hove Albion in the U18 Premier League, keeping just three clean sheets and conceding 49 goals. He has also played two matches in the FA Youth Cup and once in the Premier League Cup for the Seagulls.Lorenz is the eldest son of the Manchester United legend, and his father's old teammates were also proud of the teenager. Patrice Evra and Robbie Keane were among those who sent a message, but Van Der Sar's message stood out as he was a legendary goalkeeper himself. He wrote:"Come on Lorenz and become the goalkeeper that you always wanted to be! Good luck and safe hands!"Meanwhile, Rio Ferdinand played 207 matches with Edwin van der Sar at Manchester United under Sir Alex Ferguson. They won the Premier League title four times and also won the UEFA Champions League once, in 2007/08.Rio Ferdinand's words about Manchester United goalkeeper should be a message for his sonRio Ferdinand spoke about Andre Onana earlier this year, claiming that goalkeepers are often remembered for their mistakes. He claimed that the Manchester United star needs to cut oout his mistakes and said (via UTD Dtistrict):"He's had a couple of moments that you wouldn't want to see on your clips. But look at the last game, he probably enabled us to win that game. People forget that. Amad got the hat-trick, but he made two unreal saves before that to actually keep us in the game. But goalkeepers live and die by big glaring mistakes. He needs to cut them mistakes out if he wants to continue."Andre Onana has been under pressure at Manchester United and the Red Devils were linked with numerous goalkeepers this summer. Emiliano Martinez was reported to be one of the top targets, while Barcelona's Marc-Andre ter Stegen was also said to be on their radar.