Saudi clubs have gained a lot of popularity since Ronaldo and Benzema joined the SPL from the European League.
With approaches from Middle East nations, they aim at long term and they shown it with their approaches for education, economics and now I believe they are doing this with football. They have a longer plan and more sustainable strategies for Saudi Professional League. I really believe that they are executing it with a plan like for 10 or 20 years to change their leagues and local player quality completely.
Japan and J-league are good case studies for Saudi Arabia to believe that they will successfully upgrade their league like J-league after a few decades.
These two legendary players have other players to join the SPL who are thinking of joining the Saudi club. Bayern Munich legendary player Sadio Mane Al Nassr is likely to be signed. Reports have revealed that representatives of the former Liverpool star have met with Al Nassr club officials. If the deal is completed, Sadio Mane could be seen at the Saudi club in the Middle Eastern country. The SPL are offering huge sums of money to sign good stars which are attracting players to come to Saudi clubs.
Big clubs need money from transfers to rebuild their squads and it's nothing better than selling old players at very good transfer prices to Saudi Arabian clubs and use that transfer income to buy new players.
From player side, when they are old and already got some achievements in Europe, they have nothing to lose by moving to Saudi Professional League just to play a very last seasons in their career.