The 26-year-old is out of contract on Tyneside at the end of the campaign and talks over a new deal reportedly broke down last season, meaning he could be on his way out of the club in the summer.
He has fallen out of favour in recent weeks, with January signing Mathieu Debuchy stepping in as the manager's preferred right-back.
But Simpson got a rare chance in the UEFA Europa League last week, starting the 1-0 win at Metalist Kharkiv.
The defender admits he has found the last few months tough but insists he still has a good relationship with Pardew and is ready to give his all when called upon.
He told the Daily Mirror: "I'm a professional footballer and I'm a Newcastle player now. There's three months to go and all I can do is train hard every day.
"It's been a tough few months but I've got a good relationship with the manager. He knows my situation with the club.
"It was good to repay him by playing my part in getting a win.
"I said to the manager whatever happens - injuries, suspension or whatever - he can rely on me if he does need me.
"That's all I can do, concentrate on training, and if I do get picked for the Europa League I've got to perform. Once the manager picks me and I'm on the pitch it's up to me to show what I can do. We'll just have to see in the summer what happens."