Liverpool looked to be heading for victory against Bournemouth, leading 3-1 with just 14 minutes of normal time to play, but Bournemouth stunned Jurgen Klopp's side, scoring three times within 15 minutes.
The Reds opened the scoring in the first half through Sadio Mane. The Senegalese forward latched onto a ball from midfield and poked past Boruc when through on goal.
Liverpool went 2-0 up thanks to a wonderful finish from Divock Origi. The Belgian took the ball round Boruc and manage to finish from an incredibly tight angle outside of the area.
Bournemouth pulled one back when Callum Wilson scored from the penalty spot, after Milner fouled Ryan Fraser in the area.
However, Liverpool's two-goal lead was restored when Emre Can curled into the top corner from just outside the area.
With 14 minutes to play, Bournemouth staged a quite incredible comeback which has been dubbed 'IstanBournemouth' by many, in reference to Liverpool's comeback in the 2005 Champions League final.
Young winger Fraser pulled one back for the Cherries firing into Karius' bottom-left corner, before defender Steve Cook scored from a set-piece, bringing the ball down brilliantly, turning then stabbing a half-volley past Karius.
Liverpool did have a chance to win the game after Bournemouth equalised when Origi fired an effort on the turn just over the bar, but the comeback was completed when Cook tried his luck from distance and Karius could only parry the ball to Nathan Ake, who bundled the ball home and sent Bournemouth fans into raptures.
Victory for Bournemouth sees the Cherries stay in 10th with 18 points from 14 games, while Liverpool squander a chance to go second and one point within Chelsea and find themselves staying in third, four points off the Premier League summit.