Jose Mournho welcomes his former employers to the Tottenham Hotspur Stadium on Sunday.
The Portuguese boss managed Chelsea to three Premier League titles, an FA Cup and three League Cups during two spells in charge at the club.
Mourinho has had a decent start to life at Spurs, with his side winning four of their last five league games.
Here's everything you need to know about the match:
Where and when is it?
The game takes place at the Tottenham Hotspur Stadium on Sunday, December 22.
What time is kick-off?
The action gets underway at 4.30pm.
What channel is it on?
Sky Sports Main Event and Sky Sports will both show the match live, with their coverage starting at 4pm.
Quotes corner
Tottenham boss Jose Mourinho told SKy Sports: "I'm relaxed because I got this club exactly as I was expecting.
"I expect to be asked about Daniel Levy saying we don't plan to spend a lot, and people to ask if I'm upset.
"Will that upset me? No. I knew it, he told me! Everything was crystal clear, no secrets in any of the club's plans, and this makes me happy.
"I don't like being at a club and being surprised by things. Here there are no surprises.
"Would I prefer to have £300m in January? I wouldn't. In January I don't need players."
Chelsea manager Frank Lampard: “When Jose first came to Chelsea, he was the first one who made me feel very close to him, working on the mental side, giving me that confidence. You form a bond.
“Working with the younger players now, it’s my duty to forge that same bond with them. They’re starting their journeys, their careers, and need to look up to me and the staff.
“It’s a constant. How you are with them every day. How much you want to work with them on the training ground. How much you delve into their personal lives, and how they interact with you. That’s huge.
“You don’t lose it as you get older. Maybe it’s slightly easier for a young manager to be aware of issues such as social media.
“But if you’ve got it personality-wise, you’ve got it.”
Betting odds
Tottenham win: 13/10
Chelsea win: 15/8
Draw: 5/2
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