Arsenal defender Takehiro Tomiyasu said he hopes to be allowed time to rest and recover before returning to club action.
The former Bologna man made his first start of the World Cup in the last-16 match against Croatia after coming off the bench in the group stage victories over Spain and Germany. He played the full 120 minutes as the game against the 2018 finalists went the distance, but Japan came out second-best after a penalty shoot-out.
Tomiyasu wasn't thrilled with his own performance in the game, with Tottenham's Ivan Perisic forcing extra-time after Daizen Maeda fired Japan in front. Arsenal aren't back in competitive action until Boxing Day, but it remains to be seen whether the 24-year-old will be involved.
"It was not enough, we did not deserve to win," Tomiyasu told reporters after the defeat. "We were so close to achieving our aim. They were better than us. I can’t be proud, I am not satisfied about what happened. This is football & we need to be much, much better.
"‘I don’t know [when I'll be back]. Hopefully I can get a bit of rest. I need time to forget about football. I need a bit of time."
Tomiyasu started as a right-sided centre-back, after Ko Itakura - who was first choice in the group stage - picked up a suspension. However, after seeing Croatia left-winger Perisic find the net, he called his own performance "a disaster".
Maeda's goal against Croatia was the first time Japan scored the opening goal in a game at this year's World Cup. They couldn't hold on, though, with Perisic finding the corner with a header to take the game towards extra-time and then penalties.
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Livakovic, who had conceded just twice in the tournament from open play, saved from Takumi Minamino, Kaoru Mitoma and Maya Yoshida. Marko Livaja was off-target for Croatia, but the European side converted all of their other penalties to win the shoot-out 3-1.
As Tomiyasu prepares for his eventual return to London, Croatia are getting ready to take on favourites Brazil on Friday. Tite's team beat South Korea 4-1 in their last-16 tie, with all four of their goals coming before half-time.
Arsenal went into the break top of the Premier League table, and will resume with a Boxing Day game at home to West Ham United. They sit five points clear of closest challengers Manchester City, but an injury sustained by Gabriel Jesus during the World Cup could be problematic.
The summer signing is expected to miss up to three months with a knee problem picked up in Brazil's defeat to Cameroon in their final group game. Arsenal have reportedly opened talks over the possibility of bringing the striker home, while they may be able to look for attacking reinforcements during the January transfer window.
