Frank Lampard has been named Chelsea's new head coach to replace Maurizio Sarri, returning to the club where he spent 13 years as a player.
The legendary midfielder, who won 11 major honours during his playing days at Stamford Bridge, takes over from Sarri following the Italian's return to Serie A with Juventus.
Lampard has just one year of managerial experience gained at Derby County but returns to the Blues on a three-year contract.
"It gives us great pleasure to welcome Frank back to Chelsea as head coach," said Chelsea director Marina Granovskaia.
"Frank possesses fantastic knowledge and understanding of the club and last season, he demonstrated he is one of the most talented young coaches in the game."
He guided Derby to the Championship play-offs last season, earning praise for his style of play, only to suffer a 2-1 defeat to Aston Villa in May's final.
The Rams granted the Premier League outfit permission to speak to Lampard, 41, last week and excused their manager from the first two days of pre-season training to avoid a long-running saga.
Chelsea have reportedly paid £4million in compensation to secure new leadership of a team that won the Europa League and finished third in the top flight last term.
Eden Hazard has since left and a two-window transfer embargo is set to force the London club to rely more heavily on its academy.
Lampard scored a club record 211 goals for Chelsea, while only three players have made more than his 648 appearances for the club.
His first competitive match in charge is away to Manchester United in the Premier League on August 11, with the UEFA Super Cup against Liverpool to follow three days later.
Derby, who are tipped to turn to Phillip Cocu, announced that assistant Jody Morris and coach Chris Jones have followed Lampard to Chelsea.