The story in question is Jack C. Haldeman II's "Home Team Advantage" as seen in Alien invasion: aliens create a game and challenge humans and available in the Internet Archive.
The game is against the Arcturians with the stake being the right to eat all humans.
Not after the Arcturians won the
series and ended the season. Not after they won the right to eat
all the humans.
The injury in question was a "trick ankle"
"Don’t blame Lefty. He couldn’t help it. Got a trick ankle, that’s
all.”
The primary humor of the piece is that the narrator discusses the loss just like any other game. The humans do get the last laugh courtesy of Julius Hawk, the announcer, chosen as the first human to be consumed, with the first bite taken out of his nose.
Undigestible, was the conclusion, unchewable; humans were definitely inedible. Something else would have to be arranged.
Slugger smiled to himself, thinking ahead to next season. You
had to hand it to the Hawk; he was one tough old bird.
It is possible I instead read the story this is apparently a sequel to, "Louisville Slugger", but this one has all of the details I recall.