The Poland international was unhappy with Pardew's decision to haul him off less than an hour into the Baggies' eventual 4-1 defeat at The Hawthorns.
Krychowiak allegedly swore at his manager in a foul-mouthed rant, which he has since apologised for, but it has not prevented the on-loan Paris Saint-Germain ace from being docked a hefty chunk of his monthly wage - a six-figure sum, according to The Sun.
"Grzegorz has come and apologised to me on Tuesday and to my staff, which is unusual," Pardew told reporters at Friday's presser. "I said to him sometimes an apology is not enough so I have fined him. I also said I don't ever want to see it again."
Krychowiak has been used 22 times in the Premier League by Albion this season, including in each of their last seven games - all ending in defeat.