Bryan Ruiz says he is blocking out the chaos at Sporting CP, where several key players have cancelled their contracts with the Portuguese side.
Many of the club's biggest names are departing due to a feud with president Bruno de Carvalho and a violent attack by their own ultras at their training ground.
Ruiz is among the group leaving the club, though he will depart as a free agent in July rather than having to cancel his contract.
Aleksandar Kolarov's free-kick proved the difference in the game, but Ruiz still seemed relieved to turn his focus away from the turmoil of club football.
"The Sporting situation isn't in my mind. I am out of contract so I have no problems with any of that," said the former Fulham playmaker.
"I will take my decision on the next club after this World Cup and that's the only thing. I feel good, I prepared myself as best as I could.
"We were hoping to get a better result. We were hoping to, at least, not lose. It is a pity that we had a couple of openings before they scored to make it 1-0. We didn't take them and after they scored a great goal. We tried to go forward together to get it to 1-1 but we couldn't do it."
Costa Rica were one of the biggest surprises of the 2014 World Cup, advancing to the quarter-finals after topping a group that also contained England, Italy and Uruguay. Ruiz believes his side still have the same togetherness that helped them achieve such success four years ago.
"I felt good going into this tournament. We play as a team and we don't play as individuals," Ruiz said. "I think that's our strength and has been for a while and we will keep doing that. Myself, I just try to do my best and I think in the next few games I will feel even better."