Inter Milan and Barcelona played out a goalless draw in their Champions League group stage opener on Wednesday, with Samuel Eto'o and Zlatan Ibrahimovic failing to make an impact. Ibrahimovic returned to the San Siro for the first team after joining Barcelona from Inter in a swap deal that saw Cameroonian striker Eto'o move in the opposite direction. The Swedish international, who spurned an early opportunity, was kept at bay for the majority of the game. He was also booed by Inter fans. "It is never easy playing against Italian teams but I'm very proud we tried to win the game. We lacked a bit of precision," Barcelona coach Josep Guardiola told a news conference. Eto'o also failed to threaten his former employers, thanks to an organized Barca defense. Inter came close when a powerful shot by Serbian midfielder Dejan Stankovic, who came on as a second-half substitute, went just wide. Both sides barely created clear-cut chances as the Group F encounter ended all square. "From the bench I saw two teams with great respect for their opponents, two teams well-organized in defense who gave little away," Inter coach Jose Mourinho commented.