Liverpool's back-line looked watertight earlier in the season. They weren't conceding chances, let alone goals. Yet their vulnerability in defence was alarming against West Ham.
They have now kept one clean sheet in their last seven games in all competitions. Liverpool let West Ham players run off them time after time, and Michail Antonio scored the home side's leveller from a set-piece as a result.
Another free-kick, whipped in from a similar position, should have resulted in Declan Rice heading in to give the Hammers a 2-1 lead.
There is an argument Naby Keita was blocked by Mark Noble for Antonio's goal, but Jurgen Klopp would have been addressing their defensive frailties at half-time.
We all know about Liverpool's injury problems. They were without Jordan Henderson and Georginio Wijnaldum for this trip to the London Stadium and both were missed. In defence, Liverpool were missing Joe Gomez, Dejan Lovren and Trent Alexander-Arnold.
James Milner was selected at right back, up against West Ham's best player Felipe Anderson. It all made their decision to let Nathaniel Clyne leave on loan for Bournemouth even more surprising.
Klopp had to hope his squad players would step up in the absence of his regulars. Manchester City responded after losing to Newcastle by beating Arsenal comfortably.
After Liverpool's 1-1 draw with Leicester, which meant they missed the chance to take a seven-point lead over City, this was a let-down.
It is important to remember there is still a third of the season to go. I recall when I won the Premier League title with Blackburn in 1994-95, we were six points clear with four games to go, but were only crowned champions on the last day of the season.
This match was a chance for Liverpool to get their confidence back, but we were left asking questions about their defence.
