it will be difficult for sure, but not hard. What you can do is set up some focus points. Mid court, far end, close end, etc. Then learn where your focus ring would be in anticipation. You wont get as many of the quick snag shots, but if you set up enough you can get some decent stuff. I would also shoot wide instead of tight, your chance of getting in focus should be better and then you can crop as needed.
If you have a chance to get one of those focus helpers or make one that can help. Its an attachment to put on your focus ring to help you find the relative position of the ring so you know that straight up is x distance and 90 right is x distance, etc, etc. Generally they are for video shooting, but can be used for photos as well.