The 56-year-old Argentinian won a legion of admirers over the 2011/12 season for guiding the Basque team to the finals of both the Europa League and the Copa del Rey, as well as a 10th-placed finish in La Liga.
A statement on the club's website read: "Athletic Club and coach Marcelo Bielsa have agreed to extend the contractual relationship that unites both parties until June 30, 2013."
Barcelona will wear this new home soccer jersey next season. They also have a new away jersey. Get them both.
Jamaica is in need of a win against the U.S. Get the jersey of the Reggae Boyz.
Germany is one of the top teams ever and they will play the US on Sunday.
England will debut their new away jersey against Brazil at the Maracana Stadium on Sunday. Get in the Gear
Support the USA national team with an official 2013 Centennial soccer jersey from Nike. Its Official.
The hoop soccer jersey is classic and cool. The USA hooped jersey is perfect for every fan. Get in the Gear.
Neymar's move from Santos to Barcelona is no doubt the biggest summer transfer.
Manchester City will try and win back the Premier League title with this new soccer jersey from Nike!
The Nike Hypervenom is the latest cleat silo from Nike. It will change your game and is worn by the game's top players.
The adidas Nitrocharge is the most talked about new cleat in years. It was released on May 15 and will take your pitch by storm.