Lee and Watson join Saints
Published 01/07/2014 | 11:52
Meanwhile, Martin Hunter has been appointed as technical director after spending four years in charge of the development squad.
Lee had been set to leave his post at Bolton's academy and work as number two under new Brighton manager Sami Hyypia, the former Reds defender.
However, the 55-year-old opted to take up the offer from St Mary's instead.
Saints are looking to move the club on following the departure of former manager Mauricio Pochettino to Tottenham, while Adam Lallana, Rickie Lambert and Luke Shaw have also left St Mary's.
"I am extremely happy that we have been able to appoint three highly-respected and talented coaches to these important positions in our coaching structure," said the former Charlton boss.
"Sammy has a wealth of experience from his time with Liverpool and Bolton, as well as from his long association with the England team.
"He will work closely with Ronald, Erwin and Jan, and will play a big part in the day-to-day coaching of the first team.
"Despite his relatively young age, Dave has already built up an impressive CV and is regarded as one of the most talented goalkeeping coaches in Europe, and has only just returned from the World Cup finals.
"That we have been able to attract Sammy and Dave to Southampton is testament to our ambition to continue growing as a club, and shows our commitment to develop talented footballers at all age levels."
Lee, meanwhile, feels he has plenty to offer the new Saints manager.
"I was thrilled to be offered the job at Brighton and I was excited at the prospect of working with Sami Hyypia again, but, totally unexpectedly, I have been given an opportunity to work in the Premier League," Lee told seagulls.co.uk.
"I fully appreciate that this is not an ideal set of circumstances and I am very sorry for the inconvenience and any embarrassment my change of mind, after the announcement was made, has caused.
"However, at this stage of my coaching career, the opportunity to work again at the very top level of English football was not something I felt I could turn down.
"I hope everyone at Brighton can understand the difficult predicament I found myself in and why I made this decision."