The limit is 20 games. If you play more during one season or over a stretch of a couple of years you are not a rookie any longer.
and btw.. it's regular season + playoffs. So if a player plays 4 regular season games and 16 in the playoffs he is not a rookie.
What? Isnt Rookie of the year award given to the best rookie in the regular season? Typical Sweden to include the playoffs as well, they do that when they try to find the scoring king and most games ever in the SEL etc, Magnus Wernblom was just recently awarded for his 628 game in the MODO jersey, has he played 628 SEL games? NO