Scotland and Wales' hopes of qualifying for Euro 2025 hang in the balance heading into the second leg of their play-offs, while it would require a monumental result for Northern Ireland to book their spot at the tournament in Switzerland.
Northern Ireland suffered a 4-0 defeat to Norway in their first leg, while Wales were held to a 1-1 draw by the Republic of Ireland and Scotland played out a goalless stalemate with Finland.
The ties, which are played home and away over two legs, will go to extra-time and penalties if the scores remain level.
European champions England, who have already qualified for Euro 2025, beat the United States in their first friendly during this month's international break and take on hosts Switzerland in their next game on Tuesday (19:45 GMT).