The Professional Footballers' Association (PFA) has labelled the damage caused by the "very serious mistakes" of Adam Johnson "extremely disappointing".
Johnson was found guilty of one charge of sexual activity with a child on Wednesday, having earlier been cleared of a similar charge at Bradford Crown Court.
The former Sunderland winger had already pleaded guilty to one count of sexual activity with a child and one of grooming on the opening day of his trial on February 10.
Johnson, whose contract was terminated by Sunderland following his guilty plea, faces up to 10 years in prison with a starting point of five years, although he intends to appeal.
Following the court's ruling, Sunderland released a statement refuting claims that the club knew of the former England international's intention to plead guilty.
And a PFA statement released on Thursday read: "The PFA notes and respects the Crown Court's decision in the trial of Adam Johnson.
"Players are role models and as such have a responsibility to behave in an appropriate way. It is extremely disappointing to see the damage caused by the actions of one of our members. Adam has clearly made very serious mistakes and in due course the Court will determine his punishment.
"As the players' union we are very conscious of the role and responsibility of our members and we work hard to ensure they receive relevant information and important guidance regarding appropriate standards of conduct.
"Personal integrity relates both to the way an individual treats him or herself as much as it relates to how he or she treats other people, with mutual respect and consideration being key to this.
"The PFA works with The Football Association, the Premier League and the Football League to develop a framework of rules for the game and these clearly define integrity issues relating to, for instance, betting and doping and to complement this, the PFA has worked with these stakeholders for some time to provide training courses on lifestyle guidance to all young players. This covers appropriate standards of behaviour encompassing the law of the land and includes a range of areas including addiction issues and sexual conduct.
"As a natural extension of this, the PFA has developed over a period of time a training programme incorporating the theme of personal integrity for all professional players; ensuring they are fully informed on such issues and includes sexual consent, standards of behaviour and respectful relationships in person and on social media. This has been developed with input from groups including Rape Crisis, White Ribbon and Women's Aid.
"Situations such as this, unfortunately, demonstrate that this is a vital area for our focus and that there is still much work to do.
"The PFA intends to make no further comment."