McCarthy may not feature this weekend but he will get to experience what it is like to be in and around the senior England team setup, which is likely to boost his confidence.
After a good end to last season and a positive start to this campaign, it would have been no surprise to see Forster battle it out with Joe Hart for the number one jersey during the upcoming national team matches.
Hart's future is up in the air at the moment after leaving the Premier League to join Torino. This time may have been ideal for Forster to try and secure his place as an England regular. He will now have to wait until he has recovered from this latest injury. It has not yet been confirmed how much action the former Celtic 'keeper will miss.
McCarthy call up
The new Southampton signing joins Hart and Tom Heaton as the third goalkeeper in Sam Allardyce's first England squad. The 26-year-old has only ever featured three times for the under-21 side.
The shot-stopper has been drafted in as cover and is unlikely to feature in England's next set of games.
Sitting on the bench
McCarthy signed for Southampton earlier in the summer and is yet to feature in a game under Claude Puel. He was brought into the club as a number two to Forster.
It is not the first time McCarthy has warmed the bench in recent times. Before joining the Saints, he was also backup at Queens Park Rangers. In fact, the last time McCarthy was a number one was back in the 2013/14 season at Reading.
McCarthy is likely to get his first Southampton appearance after the international fixtures are over.