The veteran forward wants to earn a new contract at the St. James’ Park club.
However, he has been besieged by one niggle after another over the past year.
He came back last month, but is now set to be out for at least a few weeks with a new hamstring injury.
"Despite all the hard work I've put in pushing to get back to full fitness, I need to take a little step backwards unfortunately guys," the striker wrote on social media.
"Frustrating as it is for everyone out there waiting for my return and to be able to help the team, these shortcomings also upset and frustrate me more than anybody else.
"I will and I am doing everything in my power to rediscover the best version of myself and finally get off this emotional rollercoaster, which I'm hoping 2025 will bring. Appreciate the patience, love and support from all those closest that know how hard I really work and how professional I always am."