Jurgen Klopp praised Liverpool defensive display in their 2-1 victory over Hoffenheim - but the German coach could not hide his frustration at their failure to keep a clean sheet.
Trent Alexander-Arnold's free kick and an own goal from Havard Nordtveit put Liverpool in command of the Champions League play-off. But a late Mark Uth strike halved the deficit and brought Hoffenheim right back into the tie.
Heading into Tuesday's clash, Klopp's back four was again under the microscope following their 3-3 draw with Watford on Saturday - when their problems defending set pieces were exposed once more.