Saints duo Maya Yoshida and Artur Boruc are likely to be in action for their respective national teams later today.
Yoshida is set to line up for Japan in their vital 2014 FIFA World Cup qualifier against Australia, which kicks off in Saitama at 11.34am BST.
Boruc, meanwhile, is in the Poland squad for a friendly versus Liechtenstein taking place in Kraków at 8pm BST.
Japan could well today become the first side other than hosts Brazil to qualify for next summer's World Cup finals.
The Samurai Blue will qualify from the AFC Fourth Round qualifying Group B if they avoid defeat to Australia or fifth-placed Iraq do not beat Oman later in the day.
Yoshida's side had an opportunity to qualify back in March but their 2-1 defeat in Jordan meant they had to wait an extra few months.
Japan's preparations for this morning's match suffered a blow last Thursday, though, as they were beaten 2-0 by Bulgaria in a Kirin Challenge Cup 2013 friendly at the Toyota Stadium.
Defender Maya, who had not played for Saints since a 3-0 defeat to West Bromwich Albion on Saturday 27th April 2013, started that game but was one of four players substituted at half time.
Boruc, meanwhile, linked up with Poland over the weekend ahead of tonight's friendly against Liechtenstein and a 2014 FIFA World Cup qualifier in Moldova on Friday.
The goalkeeper has taken hold of the number-one jersey since being recalled to the national team in January.
Tonight's game against Liechtenstein – 148th in the current FIFA rankings – should be an opportunity to build confidence ahead of that tricky qualifier in Moldova.