Stanford University "Cardinal"
It's a rare and pleasant surprise to discover a sports writer who correctly understands the names of sports teams — their brand names and how we should talk about them — and reflects that understanding in his/her articles.
Example…this excellent piece in The New York Times about the Stanford University "Cardinal" — not Cardinals — and the school's outstanding football quarterback, Andrew Luck.
Pay special attention to the writer's use of an apostrophe when she says "Cardinal's"…"Cardinal's game…Cardinal's victory," etc. Major kudos to Karen Crouse!
If the brand name of the team was "Cardinals" rather than "Cardinal" the apostrophe would follow the "s"…"Cardinals' game…Cardinals' victory," etc.
As I have said before — and will repeat forever — the names of sports teams that end with the letter "s" do not mean that the names are plurals for multiple players. Instead, they are registered brand names; so an individual player is not the team's brand name minus an "s". Hence, Derek Jeter is not a Yankee.