I don't think Ronaldo has ever regretted joining Al Nassr they had enough good intentions so it was their choice, I know Ronaldo still failed this season because he couldn't bring any trophies and this club failed in all competitions but that doesn't mean Ronaldo has regrets because that and of course he has made a lot of contributions including to the team and also the fans are glancing at this SPL league.
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Even though he hasn't been able to provide a trophy for Al-Nassr, Ronaldo has been successful enough to prove that he is still productive in scoring goals. In 16 matches with Al-Nassr, Ronaldo managed to become #2 as the top scorer of the clubs under Talisca. he success with 14 goals, while Talisca with 20 goals. So, it is not impossible that next season with a full playing schedule, Ronaldo can give his first trophy for Al-Nassr. So far there has been no disciplinary action reported. This means that he has no regrets about his decision to play at Al-Nassr.