Fantasy Premier League: Which key players are set to miss matches?
Both tournaments begin in the second week of January and last for around a month and - depending on how their respective nations get on - some players could be unavailable between Gameweeks 21-24.
The big absentees are Liverpool's Mohamed Salah (£13.3m) and Tottenham's Son Heung-Min (£9.9m) - the two biggest point scorers so far this season.
The pair are in the top five for ownership percentage, making them among the most popular picks and meaning plenty of managers will need to make moves to offload them.
Jarrod Bowen (£7.9m) is likely to be a popular replacement given his recent form for West Ham as is his teammate Mohammed Kudus (£6.8m), despite the latter soon departing to play for Ghana at AFCON.
The kind-looking fixtures for Arsenal mean Bukayo Saka (£9.0m) and Martin Odegaard (£8.4m) are solid options, but the former's high ownership shows he is in plenty of squads already.
Chelsea's Cole Palmer (£5.6m), Son's teammate Richarlison (£6.8m) and even Manchester United's Alejandro Garnacho (£4.7m) at lower price points could also prove tempting with the cash about to be freed up.
Some other notable departures are United goalkeeper Andre Onana (£4.8m), Brentford forward Yoane Wissa (£5.8m) and Chelsea's Nicolas Jackson (£6.9m), while Wolves' Hwang Hee-chan (£5.7m) is set to join up with Son and South Korea.
Gameweek 21 begins on January 13th with matches spread across two weekends as part of the Premier League's winter break.