Germany coach Joachim Low has backed Mario Gotze despite his difficulties following last summer's return to Borussia Dortmund from Bayern Munich.
Gotze, 24, has struggled to find form and has played only 24 minutes in 2017, also suffering muscular problems.
But Low stressed that he would continue to call the midfielder up for Germany and told kicker: "Mario can make the difference."
"Mario's situation at Dortmund is not that easy right now, but I know that he's incredibly ambitious and totally focused on football.
"He trains hard, and subordinates everything to competitive sport. He's predominantly showing good performances when he's with us, and that's important for me.
"Even when he's not in his best shape at the club, I know what he can do for us."
Gotze, 24, faces a race against time to be back to full fitness for the second leg of the Champions League tie against Benfica in which his side are a goal down after the first game.
He scored the 2014 World Cup final winner but recently said he no longer saw himself in an attacking role.
But Low said he valued Gotze's attacking threat and added: "He's not a striker in a classical sense, but a finisher.
"He scores goals against top nations -- he has the gift to score at the highest level, and not everyone can do that."
Looking ahead to the 2018 World Cup in Russia, the national coach said that, for all the talent coming through at club level, he would be banking on players already accustomed to the pressure of big tournaments.
"If someone shows good performances in the Bundesliga it does not automatically mean that, in the knockout matches at a World Cup, he can access a performance the team needs to win the title," Low said.
"We are talking world class, absolute world class. We need [Manuel] Neuer, [Mesut] Ozil, [Mats] Hummels, [Jerome] Boateng, [Toni] Kroos to win the World Cup."