Massimo Maccarone regrets turning down Giovanni Trapattoni to stay working with Gareth Southgate, describing the now England manager as "big talks, no facts".
Former Italy striker Maccarone spent four years as a team-mate of Southgate's at Middlesbrough, before playing his final six months at the Riverside Stadium under the tutelage of his former captain.
Maccarone had found himself out of favour under former boss Steve McLaren but was convinced to stay when Southgate took over ahead of the 2006-07 season.
But Maccarone made just one Premier League start and seven top-flight appearances in total before leaving for Siena in the January transfer window.
Southgate, who oversaw Boro's relegation in the 2008-09 campaign, has earned plenty of praise for his work with England, who he led to the World Cup semi-finals in Russia in 2018.
However, Maccarone was disappointed with his own personal treatment.
"I played the last seasons of his career with him and as a player he has always been correct, kind, humble," he told Stats Perform.
"As a manager, though, I didn't like very much what he did to me. Besides I had already had some quarrels with his predecessor, Steve McLaren, another one who has managed England, when I reacted berating him a lot and then in hindsight I understood I had made some mistakes myself too.
"But not with Southgate who talked me a lot into staying at Middlesborough, promising I would have played a lot since he knew well what had happened to me the season before.
"But then, nothing even if we made seven points in the first six games. Big talks, no facts."
If things had played out differently, Maccarone could have been playing for Salzburg under Trappatoni, the man who had given him his Italy debut.
"When I was in England he was managing Salzburg in Austria," he added.
"He had called me for one month to convince me to join him there but I still had a one year contract with Middlesborough and I wanted to prove myself there after a negative season despite some sparks in the UEFA Cup.
"So I stayed with Southgate at Middlesborough when Trapattoni had made my dream of playing for Italy come true."
Asked if that is a decision he now regrets, Maccarone replied: "In hindsight yes.
"But Southgate had been my team-mate and captain for four years. He kept telling me, 'I can't understand why [McLaren] doesn't let you play' but then when he became the manager he truncated my career at Boro.
"I said no to Trapattoni for Southgate but I should have done the opposite."