It can't possibly be counted as a 0 rating. If it were, his season average rating at the time of your linked screenshot would've been 4.83 (either represented as a 4.5 or 5.0, I'd guess), not the 5.5 that it is.
Remember, Scrimmage and Cup games are
not included in this calculation. I have a PF who barely plays in competetive games at all, and for quite some time his only league match had him on the court for only 2 minutes. In his season stats, that game showed no rating, yet his season total average rating was 5.0. He has now played in 2 competetive games, for a grand total of 8.7 minutes. In the latest game, his star rating was a 7.0. You can view his average season stats for yourself
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