Manchester United dropped their pursuit of Matthijs de Ligt before Ajax's run to the Champions League semi-finals, because of concerns about his weight, ESPN reports.
The 19-year-old defender is believed to be on his way to Barcelona this summer.
Even before this season, De Ligt was one of the most highly-rated young players in Europe and was discussed as a possible target by United.
However, prominent members of the recruitment team voiced worries that De Ligt, who lined up against United in the 2017 Europa League final, was vulnerable to gaining weight because of concerns about his family history.
While United have retained their interest, Barca are leading the chase for De Ligt, after Ajax CEO Edwin van der Sar confirmed the teenager is likely to leave this summer.