There is a growing issue of religious practice and it's conflicts with employment in the USA. Wal Mart, other business, as well as government agencies have had managers, other employees have conflicts of faith vs. work. Growing numbers of dedicated Christians do not want to work at all on Sunday or Jews working on Saturdays/Friday nights. In many ways, they are protected by civil rights laws, but still it may make you look uncooproative and affects your future employment or advancement.
The difficulty for Sean Green here is that his team, the Dodgers, are playing against their division rivals (SF Giants) for 1st place in their division or the 1st choice for the wild card spot in the playoffs. If they were playing a celler dweller, then probably he would have taken both the Friday Night and Saturday day game off.
His decision to at least take the Saturday off (a national FOX network TV
game) shows a balance of his faith and the team needs. He has taken very few days offs as a player in the Majors, so for him to take a day off for a reasonable faith holyday is no problem for me, nor should it be for anyone else.