Signed for an initial 12 months last July from Borussia Dortmund, Moyes has ruled out making a bid to secure his services permanently during the next transfer window but admits Pienaar is doing his case to stay on Merseyside no harm at all.
"Steven has been really impressive in the last six weeks," told the Liverpool Echo. "He has played really well and we have been pleased with what he has contributed to the team. He is a very good footballer.
"He takes the ball and creates chances but I also like the work ethic that he has too. He's getting better and better and has helped us improve with his play. He, like the other midfielders, is right on top of his game.
"We need it that way, though. When Mikel Arteta was injured at Chelsea a couple of weeks ago, we struggled a bit but hopefully everything will be okay for tomorrow. They are all good players and are helping us play a certain way.
"We have got him for the year and we hope that he can carry on as he has been doing. We won't be doing anything soon.
"We will get to the end of the year and when his loan is finished we will look at things then."