Swansea currently sit ninth in the table, which would equal their best Premier League finish, achieved in 2012-13.
But after a disappointing display at The Hawthorns - during which his side appeared devoid of ideas and fell to goals from Saido Berahino and Brown Ideye - Monk is well aware that Swansea could yet squander the opportunity to finish higher up the league than ever before.
"It's a critical moment for us," he told Sky Sports.
"We are in a position where we can achieve things that we haven't done in this league before and it is up to the players and myself to make sure we amount to that, but performing like that [against West Brom] won't get us to where we want to be.
"Hopefully we will bounce back, we have a tough game at home against Manchester United."
Monk will hope for improvements across the board in that next league match after watching his side fall short all over the pitch against West Brom.
Monk added: "We lacked in all areas.
"There wasn't much in it first half, but second half we just didn't have that intensity, the passing wasn't sharp enough, which is so crucial to the way that we play, that allows us to create or be in positions to create and score goals and we didn't do that enough at all.
"That's the reason why we lost the game."
