Both Pompey and Southend will show their support for the Offside Trust today by wearing specially printed t-shirts in the warm-up.
And Pompey star David Wheeler took time out after training this week to show his backing for the campaign.
This is the second season that Pompey have supported the charitable organisation, which was founded three years ago to support victims of historical abuse in football and other sports.
Steve Walters, a former professional footballer who founded the organisation with golfer Chris Unsworth, said: “We are delighted to be able to mark the Offside Trust’s third birthday at Pompey. The club have been very helpful and supportive of our aims since we started.
“We are established as the independent body to work alongside clubs, organisations and other charitable bodies to further enhance safeguarding at all levels of sport.
"We are delighted to be able to mark the Offside Trust’s third birthday at Pompey."
“We’re in the process of rolling out our strategy on how the Offside Trust will combat child abuse in sport and support the healing journey of survivors. We are talking to survivors, support services, governing bodies, clubs and other stakeholders around the country.
“We are building partnerships and learning how we can make the greatest difference where it is needed most.”
Colin Farmery, Pompey’s senior safeguarding manager, said: “We take our safeguarding responsibilities very seriously at the club and we have had a close connection with the Offside Trust since it formed.
“We are really pleased that they have chosen Fratton Park to mark their third anniversary.
“Clare Martin from Pompey in the Community and I will be giving the members of the trust a talk on how our safeguarding procedures work at the club.
“We feel we do as much as we can, but in this arena it is a culture of continuous improvement and eternal vigilance.”
Fans can also show their support, as members of the Offside Trust will be holding a bucket collection before the game.
To find out more about the Offside Trust and how to support them, visit www.offsidetrust.com