Ben Jones-Bishop is set to miss the opening months of the Super League campaign after being diagnosed with a medical condition.
Wakefield Trinity released a statement to confirm that the winger has been unable to take part in pre-season training.
He is expected to be sidelined until the summer months as Trinity prepare for their Super League opener against Hull KR on January 31.
The Jamaican international's last appearance was for the Reggae Warriors as they lost to England Knights at Headingley in October.
Wakefield's head physio, Ryan Carmody, said: “Earlier on in pre-season we received the news that Bish had been diagnosed with a medical condition.
"Unfortunately it’s stopped him taking part in any sort of training and means he’s set for a fairly lengthy spell on the sidelines.
"He’s currently under investigation with the medical team and we hope to see Bish back in the red, white and blue during the summer.”
Jones-Bishop has been an ever-present member of the Trinity side since joining from Salford Red Devils ahead of the 2016 campaign.
He claimed 11 tries in 31 appearances for Wakefield last term and has scored over 60 times during his four seasons at Belle Vue.
Wakefield's preparations for the 2020 campaign continue on Sunday as they host Hull KR for Danny Brough's testimonial.
They will also face Huddersfield Giants on January 22 before travelling to the Robins at the end of the month.