Start with the definition
A goal assist, a fantasy assist and a secondary assist describe different contributions. A pass to the scorer may qualify as a conventional assist, while a rebound or a penalty won may be counted by a broader fantasy system. Adding these categories together changes the question being answered.
Keep the source consistent
For its Champions League history, UEFA lists Cristiano Ronaldo with 42 assists and Lionel Messi with 40. This site uses those UEFA figures for that competition. A different provider may classify individual incidents differently. A difference is a reason to inspect the underlying events, not to silently replace one number with another.
What our comparison includes
Our Champions League view combines goals and assists only within UEFA's published coverage. The career view uses the secondary reference’s conventional-assist totals, while this Champions League view keeps UEFA’s definition. Do not subtract an assist subtotal from a different provider’s career total.