Portsmouth chairman Milan Mandaric has sold his remaining stake in the club to joint-owner Alexandre Gaydamak for around £32m.
Gaydamak (left) wants to carry on Mandaric's legacy
Mandaric took over in 1998 but insists he will be staying on at the club as a non-executive chairman to offer advice and experience to the new owner.
"I'm not walking into the sunset. I'll help Alexandre any way I can," he said.
"I am safe in the knowledge that I place Portsmouth in the control of a person with massive ambitions."
Mandaric breathed new life into Portsmouth when he took the helm at Fratton Park, winning promotion from the Championship and establishing the club in the Premiership.
I will place Portsmouth Football Club in the control of a person that has massive ambitions and has fallen in love with the supporters
But he said he felt "intense optimism and excitement" after handing over the reins to Gaydamak, who arrived at Fratton Park in January as co-owner.
"I could not have asked for a better scenario than this one and I know that supporters are going to give Alexandre the same wonderful backing and encouragement they gave me," Mandaric said.
"I can do this all safe in the knowledge that I will place Portsmouth Football Club in the control of a person that has massive ambitions, who has fallen in love with the supporters and is someone who will take this on to the next level.
"I can look back with a great deal of satisfaction on what this club has become today but this is now the beginning and a time to look forward with intense optimism and excitement."
Gaydamak invested around £20m in the club last January which enabled manager Harry Redknapp to make a host of signings to help save the club from relegation.
That spending power has increased this summer with Glen Johnson arriving on loan from Chelsea and a number of signings expected to follow.
Gaydamak was quick to praise the work of his predecessor and told the club's website: "What Milan has done for this club is priceless
"Milan's vision, belief, hard work and compassion has laid the foundation for all that we started to do in January.
"Following in these footsteps is not easy."