(CNN) -- A goalkeeper for the German national soccer team apparently killed himself by stepping in front of a train, just months after he and his wife adopted a daughter, police said Wednesday.
Robert Enke, 32, was captain of the German top-division soccer club Hannover 96 and had played in eight games for his national team. He was widely expected to be the German team's keeper in the 2010 World Cup.
"Preliminary police investigations indicate a suicide," Hannover 96 spokesman Stefan Wittke said.
Enke died about 6:25 p.m. Tuesday. His wife Teresa said he left a suicide note.
She said her husband had been battling depression for six years but had kept his condition from the public.
"I tried to be there for him, said that football is not everything. There are many beautiful things in life. It is not hopeless," she said.
The Enkes' daughter Lara died in 2006 from a heart condition at age 2. The couple adopted a daughter, Leila, earlier this year. She is 18 months old.
Enke feared that if his depression was made public, he might lose Leila, his widow said.
"We had Lara; we have Leila. I always wanted to help him to get through it. He didn't want it to come out because of fear. He was scared of losing Leila," she told reporters.
The German national team had an exhibition game scheduled Saturday against Chile, but the team announced it was canceling the match.
Theo Zwanziger, president of the German soccer federation, said players "needed time to come to terms with the death of Enke."
Enke always said he wanted to play for the national team at the 2010 World Cup, the federation said.
"The leadership of the German national team never had any doubt that he was important for the team both as a goalkeeper and as a human being," a statement said.
Those who knew him were stunned by news of his death.
"We are in a state of shock," team manager Oliver Bierhoff said in a statement. "It is beyond words."
Martin Kind, chairman of Hannover 96, said, "It is a total catastrophe. I am finding it hard to understand. All I can say for sure is that it had nothing to do with football."
Fellow players said they believed Enke had been suffering depression, Kind said.
"He was unstable," he said, "but he kept it under wraps."
Hundreds of fans and former teammates gathered to lay flowers, light candles and sign a book of condolences outside Hannover 96's Niedersachsen Stadion. The team's official Web site has been converted into a single-page memorial.
Enke missed Germany's last four matches because of a bacterial infection, but he had recently returned to action with Hannover.
Soccer commentator and journalist Rafael Honigstein said Enke was on course to be picked as the No. 1 choice for the team.
"It's been well documented that he had a tough time," Honigstein said. "People knew it was a terrible, terrible tragedy for him."