Louis Deacon says it was "amazing" to go from playing in the back garden with brother Brett to lining up alongside him in the Leicester Tigers first team.
The ex-England lock, 34, has retired from rugby after injury has prevented him making an appearance this season.
Deacon made his Tigers debut in 2000 and won six Premiership titles and two European Cups as a one-club man.
"It was a dream for us to play in the second row together for Brett's first game," he told BBC East Midlands Today.
"It was out of the blue and pretty amazing because the club has a huge tradition of brothers playing together.
"We'd always dreamed of playing for Tigers after starting with a ball in the back garden knocking lumps out of each other."
Deacon played more than 270 senior games for Leicester and was part of the England squad to compete in the 2011 World Cup in New Zealand.
He says that having a brother also striving to reach the top of the sport really helped developed his own game.
Leicester-born Deacon added: "I suppose the only rivalry we had was that we both wanted to achieve the same things.
"When I made my debut, he wanted to make his debut, and it was like that all the way through the age groups."
Deacon admits he thought long and hard about his decision before calling it a day and has taken inspiration from brother Brett's move into coaching.
The younger sibling was forced to retire early in 2013 after a life-threatening illness.
"Brett's been through retirement already so he's given me lots of tips and he's doing very well now coaching the academy side," said Deacon.
"I could have probably carried on playing, but I didn't want to get down the line of where I couldn't do anything with my kids when I got older.
"I want to stay involved in rugby and I've been coaching the Spanish national team and also doing some commercial things at the club working in sponsorship, so I want to explore those two things."