According to ManUtd.com, the former Manchester United midfielder, who made 146 appearances for the club, has agreed to a new contract until June 2024.
Phelan has a plethora of expertise and was a member of Sir Alex Ferguson's coaching staff at Manchester United.
He was also a member of Ferguson's first trophy-winning team, winning the FA Cup in 1990, the European Cup Winners' Cup in 1991, and the Premier League in 1993.
After serving as first-team coach, he was promoted to his current position in May of the following year.
After joining United from Norwich City in 1989, he made 146 appearances for the club before joining West Brom in 1994. He was a key member of Sir Alex Ferguson's first trophy-winning team, winning the FA Cup in 1990, the European Cup Winners' Cup in 1991, and the Premier League title in 1993.
Source: transfermarketweb.com