The FA Cup is back and, after Middlesbrough knocked out Manchester United on Friday night, it's the turn of Plymouth Argyle to try and eliminate Premier League opposition.
The League One side travel to Stamford Bridge to take on the might of Chelsea, the reigning European champions, on Saturday lunchtime.
There is also a possible upset in Saturday's other early kick-off as West Ham travel to the Midlands to take on the sixth-tier National League North side Kidderminster Harriers.
Follow Sportsmail's ADAM SHERGOLD for live FA Cup fourth round coverage of Chelsea vs Plymouth and Kidderminster vs West Ham, including build-up, team news and updates.