You can't stop Luka. From watching the Mavs a lot the last two years, there are two ways to defend him. Double him every time and hope others miss open shots. Denver and Clippers had some success with this. Other approach is to live with his three-point shooting. He is a good shooter, but most (almost all) his threes are off the dribble. He doesn't get set up for open/ set three-point shots. He is also somewhat streaky, so in my opinion, you switch Ayton on him and tell Ayton to stay in front of him and then use his length to challange the shots once he jumps (Do NOT fall for pump-fakes.) Ayton had some games where he did a great job defensively on smaller guys on the perimeter.
On the other end of the floor, whoever Doncic is guarding needs to be aggressive. He is a better defender than people think, but he is not great. Run him through multiple screens on every possession. If you bang him up consistently, those step-back threes are likely to be just a little short in the fourth quarter.
Also, do not let Booker anywhere near him on defense. Luka will eat him alive. When Book gets eaten alive, he gets frustrated and starts doing stupid stuff. I love Book, but he should not look at Luka, let alone try to match up with him.
