Harlequins and Northampton Saints are the only Gallagher Premiership sides in action on Monday, December 27.
League champions Quins have made five changes for Saints' visit to London, with fly-half Marcus Smith and back-row James Chisholm ruled out due to positive Covid test results.
Saints have made three changes, including Dan Biggar returning to the team after a thigh injury.
Quins have been victorious in their last three Premiership games against Saints, after losing 11 of the previous 13, while Chris Boyd's visiting side have won their last two away fixtures against Quins.
The match follows Harlequins Women taking on Wasps Women at 2.15pm in the Allianz Premier 15s, England's top women's rugby competition.
Here's everything you need to know about the game.
What time is Harlequins v Northampton kick-off?
Harlequins host Northampton Saints on Monday, December 27, at Twickenham Stadium. Kick-off is at 5pm .
What TV channel is Harlequins v Northampton on? What about live streaming?
Harlequins v Northampton will be broadcast live on BT Sport 1 from 4.15pm, with Harlequins Women v Wasps Women (2.15pm kick-off) being shown beforehand on the same channel as they also run out at Twickenham.
BT Sport customers can also watch on the broadcaster's website or via the app.
What's the Harlequins v Northampton team news?
Fresh from two Champions Cup wins against Castres and Cardiff, the hosts' five changes see props Joe Marler and Will Collier, second row Matt Symons, fly-half Will Edwards and wing Louis Lynagh restored to the starting line-up.
As for the visitors, who lost their Champions Cup matches against Racing 92 and Ulster, Wales fly-half Biggar returns after a thigh problem, hooker Sam Matavesi starts and No. 8 Juarno Augustus also comes into the line-up.
Harlequins: 15. Tyrone Green, 14. Louis Lynagh, 13. Joe Marchant, 12. Andre Esterhuizen, 11. Cadan Murley, 10. Will Edwards, 9. Danny Care, 1. Joe Marler, 2. Jack Walker, 3. Will Collier, 4. Matt Symons, 5. Stephan Lewies (capt), 6. Tom Lawday, 7. Jack Kenningham, 8. Alex Dombrandt.
Replacements: 16. Jack Musk, 17. Santiago Garcia Botta, 18. Simon Kerrod, 19. Hugh Tizard, 20. Viliami Taulani, 21. Lewis Gjaltema, 22. Luke Northmore, 23. Huw Jones.
Northampton Saints: 15. George Furbank, 14. Ollie Sleightholme, 13. Matt Proctor, 12. Fraser Dingwall, 11. Courtnall Skosan, 10. Dan Biggar, 9. Alex Mitchell, 1. Alex Waller, 2. Sam Matavesi, 3. Ehren Painter, 4. David Ribbans, 5. Api Ratuniyarawa, 6. Courtney Lawes, 7. Lewis Ludlam (capt), 8. Juarno Augustus.
Replacements: 16. Mike Haywood, 17. Nick Auterac, 18. Paul Hill, 19. Alex Coles, 20. Tom Wood, 21. Tom James, 22. Rory Hutchinson, 23. Ahsee Tuala.
Who is the Harlequins v Northampton referee?
Referee: Wayne Barnes
Assistant referees: Anthony Woodthorpe and Jamie Leahy
No.4: Simon Harding
TMO: Stuart Terhegee
