I get so focused on their number 10 that he ends up dragging me everywhere

A number 10 can be your reference without becoming your personal opponent. If he moves out of the central space, ask what happens if you let him go. If a teammate can pick him up and the middle remains protected, holding your position may be more valuable. If he receives in a dangerous central area with nobody able to pressure him, then you may need to engage. The key is to protect the team's structure while still affecting the player. Use communication early. If he drifts towards a full-back or another midfielder, pass the information on instead of following him automatically. As the 6, getting dragged away can open the exact lane the opposition wants. Your role is often to make central progression difficult. Track movement when it creates immediate danger, but do not abandon the space in front of your centre-backs simply because one opponent has changed position.