They were running out of able-bodied defenders at Anfield.
When Lucas is forced into action as a centre-half and you end an FA Cup tie with a pair of left backs in the heart of your defence, you probably need reinforcements.
It's no surprise that Liverpool manager Jurgen Klopp has looked to Germany, but with his efforts to bring either Neven Subotic or Joel Matip to the club this month
set to be frustrated, he has instead opted for a shorter-term solution.
Klopp has completed a loan deal for QPR defender Steven Caulker that sees the 24-year-old join Liverpool until the end of the season, providing cover for an injury crisis that has seen central defenders Mamadou Sakho, Dejan Lovren, Martin Skrtel and Kolo Toure all sidelined at various points over the last few weeks.
https://twitter.com/LFC/status/686895413232799744
And Caulker could even be rushed into action in tomorrow night's vital game against Arsenal.
https://twitter.com/BSmith/status/686895954453204992
Caulker, once a target for Brendan Rodgers when playing for Cardiff, had been on loan at Southampton but only made eight appearances for the Saints this season - the last of which was the 6-1 defeat by Liverpool in the Capital One Cup.
