Joe Allen's 90th-minute strike earned Liverpool a point against Premier League leaders Arsenal.
Liverpool manager Jurgen Klopp bemoaned his side's lack of concentration and said the Reds must work on defending set pieces.
Second-half substitute Joe Allen rescued a point for Liverpool in an entertaining 3-3 draw at Anfield on Wednesday. Liverpool led twice thanks to goals from Roberto Firmino but was pulled back by Aaron Ramsey and Oliver Giroud, before the latter put Arsenal ahead early in the second half.
Giroud's equalizer came from a corner, and Klopp said his men need some work on the training ground to limit the goals they concede from set pieces.