The Dutchman believes the current AC Milan boss did not trust his fitness levels in his final season at the club and has put off retirement talk until the end of the campaign
Seedorf signed for Brazilian side Botafogo in the summer of 2012 after spending ten years with the Italian giants, and he feels he had little choice but to leave the club after Allegri lost faith in his ability to continue performing at the highest level.
"My relationship with Allegri wasn't one of the best," he told sports show Redacao. "Not because of anything personal, but he made me play all the important matches, against Juventus, Arsenal, Barcelona, Inter, and then I'd sit on the bench for four games.
"It wasn't a matter of age. When you train constantly and you play frequently, you keep yourself fit.
"He made people question whether I was fit to play. It wasn't a matter of age. When you train constantly and you play frequently, you keep yourself fit.
"[Paul] Scholes and [Ryan] Giggs were protagonists for Manchester United until last year. What happened to me was a shame."
Seedorf admits he is enjoying his time in the Brazilian top flight, and made it clear he will not make a decision over his retirement until the end of 2013.
"I knew I needed some time to adapt to Brazil, but for me, having a new motivation was really important," said the 37-year-old. "In my case, I needed to move on with joy, and I found it here in Brazil.
"I'm not putting a limit on anything. There's nothing concrete about it [retirement].
"You will know when I know. My focus right now is to play for Botafogo at least until the end of the year."