One thing I've found to work is keeping a string (hoodie cord work great just snip the ends off) coiled up on the desk. They walk in wanting attention and you toss an end at them etc. and they rawr and attack. See if that's what the lil guy wants.
I've also had tremendous luck with the circular cardboard "dish" shaped (concave) scratchers, a modern take on the classic cardboard scratcher. Somehow the act of scratching it then curling up for a nap in it appeals to the cats. Both are snoozing in them as I type 😺