EVIAN-LES-BAINS:  Germany needs to focus on its defensive deficiencies weaknesses as it prepares to play Poland, top-scorers in qualifying round for the European Championship.

The world champions opened their campaign with a 2-0 win against Ukraine but were grateful to goalkeeper Manuel Neuer for three outstanding saves and Jerome Boateng for a goal-line clearance.

Poland, which is led by qualifying's top scorer Robert Lewandowski, will present a bigger challenge for Germany's defense with both sides eyeing top spot in Group C on Thursday at Stade de France. Poland also won its first match, beating Northern Ireland 1-1.

One potential positive development for Germany is that defender Mats Hummels has declared himself fit after recovering from a calf injury he sustained in the German Cup final last month in his last game for Borussia Dortmund.

Coach Joachim Loew needs to decide whether to risk Hummels, who won't have played for almost four weeks, or continue with his stop-gap solution of Shkodran Mustafi partnering Boateng in central defense.

Mustafi opened the scoring against Ukraine but looked vulnerable at times against speedy wingers Andriy Yarmolenko and Yevhen Konoplyanka, and the Valencia defender almost gifted a late equalizer in a mix-up with Neuer.

Bayern Munich midfielder Joshua Kimmich could also fill in, as could Bayer Leverkusen's Jonathan Tah, though both players are short of experience. The 20-year-old Tah was a late call up for original Hummels-replacement Antonio Ruediger, who tore a cruciate ligament in his right knee in training.

Poland's victory over Northern Ireland in Nice on Sunday was the country's fist victory at a European Championship. The team is unlikely to be overawed having beaten Germany in qualifying  its first win over its neighbor in 19 games.

Lewandowski says it is "the best Polish team in which I have ever played."

Lewandowski is partnered in attack by Ajax striker Arkadiusz Milik, familiar to Bundesliga fans from his time at Leverkusen and Augsburg. Though Lewandowski was kept quiet against the Northern Irish — no shots on goal and just 49 touches of the ball  he created space for Milik to score the only goal.

"The goal was important, I'm really happy about it," the 22-year-old Milik said. "But even more important are the three points. We still have a few steps ahead of us; this is not the end of the journey."