Check out the former Manchester United and Tottenham stars, as they demonstrate their karaoke skills.
With Harry Redknapp's newly promoted Hoops squad on a pre-season tour of Germany this month, two of their star signings were forced to do the initiation that every football player dreads - showing off those singing skills!
Former United favourite Rio Ferdinand will play under Rednapp once more after making his debut under the 67-year-old at West Ham over 15 years ago. He joined on a free transfer from Old Trafford.
Tottenham graduate Caulker cost £8 million from relegated Cardiff City, though also knows Redknapp having emerged into a promising defender while the R's boss was across town at Spurs.
Both are England internationals, one with his career very much all ahead of him and the other hoping for an Indian summer at Loftus Road, but the two were treated equally enough, or rather, they were equally as off key.
Ferdinand rapped a line from Notorious BIG's Juicy, while Caulker sang a verse of City High's What Will You Do?
Thankfully, the duo's defensive skills are somewhat stronger than their ear for a tune, though they might point at the poor equipment on offer - an empty water bottle as a mic is never going to capture a singer's true voice after all.
Ferdinand and Caulker today made their debuts for QPR, with each playing 45 minutes of a 2-0 loss to Red Bull Leipzig.
Can Ferdinand and Caulker keep QPR up next year?