It was a stunning night at Elland Road as Derby County booked their place in the Championship play-off final.
After a 1-0 defeat in the semi-final first leg, it looked like it could be too much for the Rams to turn things around against Leeds United.
However, in a superb contest a brace from Jack Marriott, a penalty from Harry Wilson and a goal from Chelsea loanee Mason Mount sealed a 4-2 win on the night to seal a spot at Wembley.
For Chelsea fans, they would have had a keen eye on the form of Derby this season with a lot of interested parties involved with the Championship club.
Chelsea and Derby fans will love how Mason Mount and Fikayo Tomori celebrated Leeds loss
Along with Mount, Fikayo Tomori has also played a crucial part in the success that Derby are having, while Frank Lampard is at the helm and another former Blues midfielder Jody Morris is the number two.
But it is the performances of Mount and Tomori that are under such close scrutiny from the Chelsea supporters.
With the transfer ban that is looming over the club, the Blues might have to look at their current 'Loan Army' to fill the gaps in any squad numbers for next season.
Centre-back is certainly one of them with Gary Cahill heading out the door and Ethan Ampadu potentially heading out on loan next season.
While Kurt Zouma is the front runner to get a spot in the squad, Tomori is in the frame and was named Derby's Player of the Season.
Meanwhile, a creative midfielder is also something of a need for the Blues, with Mateo Kovacic and Ross Barkley failing to hit the mark in that respect.
Mount showed again at Elland Road that he has the ability to add that to the Chelsea team, should he be called upon by the Blues.
'Soon to be Chelsea legend' - Mason Mount sends fans wild with Derby County goal at Leeds United
But it is their performances at Elland Road, one of the hottest atmospheres that you are going to find in England that is the most impressive.
Mount with his goal, Tomori with the ability to stand up to the pressure and it went a long way to prove that they can handle being at Chelsea next season.
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