The defender made the commitment before heading off to represent Japan at the 2015 AFC Asian Cup, which gets under way later this month.
Yoshida departed for host nation Australia following yesterday’s win over Arsenal, but not before agreeing to extend his contract until 2018.
The 26 year-old has been with Southampton since August 2012, making 60 appearances and scoring three goals.
He has been a regular participant over the busy Christmas period, showing his versatility by playing at right-back as well as in his usual centre-back position.
Having extended his deal with Southampton, Yoshida has now headed off to help Japan as they look to defend their Asian title.
The Samurai Blue kick off the tournament in Group D, where they will face Palestine on 12th January, Iraq on 16th January and Jordan on 20th January.
The knock-out stage begins on 22nd January and runs until the final on 31st January, meaning Yoshida could potentially be away until Saints travel to Queens Park Rangers on Saturday 7th February.