NEWCASTLE Knights star Jarrod Mullen is facing a ban of up to four years after testing positive for anabolic steroid use.
Mullen has returned a positive A-sample for Drostanolone after being tested in late November.
The 29-year-old has been provisionally suspended by the NRL under its anti-doping policy after ASADA notified the club and governing body.
Under the NRL's policy Mullen can either immediately accept the results or have his B-sample re-tested.
Newcastle CEO Matt Gidley expressed his disappointment in the findings via a club statement on Tuesday afternoon.
"The club is obviously extremely disappointed,” Gidley said.
"The club has a strict governance program, the players are regularly educated and fully aware of the consequences of going outside our governance guidelines.
"From here, there is a formal process we need to follow under the guidelines.
"We need to respect the process and in the interim the club will continue to monitor Jarrod's welfare.”
The news is another hammer blow for the struggling Knights, who have run last the past two seasons and are tipped as wooden spoon favourites in 2017 as well.
Mullen's own career has been cruelled by injury to the point where his last hamstring injury prompted speculation he would be forced into early retirement.
The local junior has played 211 NRL games since debuting with the Knights in 2005, making a rapid rise to New South Wales Origin honours two years later.
But after being billed as a star the club could build around in the wake of Andrew Johns' own injury enforced retirement, Mullen has struggled to live up to a weight of expectation throughout his career.
In 2016, a hamstring torn off the bone sidelined Mullen for three months, with the latest development leaving his career in tatters.
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