During his time coaching in the UK he worked with players such as Michail Antonio, Wilf Zaha, Victor Moses and Jonny Williams.
He later moved to Thailand taking the role of academy manager at Muangthong United before becoming the club's technical director and later reserve team head coach.
It was reported that Muangthong United has sold players from their academy and B team to other clubs in Thailand for transfer fees in excess of US $6,000,000.
In 2017 Sean moved to Cambodia assuming the role of technical director for Phnom Penh Crown following the abrogation of Ukrainian Oleg Starynskyi's contract,[1] Sainsbury was re-appointed as head coach nine days later,[2] taking charge of the team for their last three remaining games (for the 2017 season) against Western Phnom Penh, National Police Commissary and Svay Rieng FC.
At the end of the 2019 season, after helping Bangkok FC to a fifth-place finish in the league, Sean was recruited by Buriram United.