It took the intervention of coach Ilderico Dias Peixoto, known as Tiu, to convince the club that they should persist with the skinny 14-year-old.
Tiu told the Daily Mail: "David has always been grateful because he knows that if it were not for me, he would have been released. He was too scrawny and playing in the wrong position.
"I tried to believe in him. They almost released him twice. The second time, he called me, crying. I asked the youth-team manager to hold on to him.
"I instructed him how to play in defence, how to get the ball, his positioning, to try to have balance, never to lose control of his emotions but to play hard. With his high intelligence and great quality, he adjusted and became a regular. I'm very proud of him now."