Conversation so far:
Did Henrik Larsson play for Barcelona?
At the end of the 2003–04 season, Larsson left Celtic on a free transfer and signed a one-year contract with Barcelona with an option for a second year.
What happened when Henrik Larsson's contract with Barcelona was over?
In December 2005, Henrik Larsson announced that at the end of his contract, which ended in July, he would leave Barcelona and return to Sweden to end his career.
What injury did Henrik Larsson get during his time with Barcelona?
On 20 November 2004, during the 3–0 victory in El Clásico against Real Madrid, Henrik Larsson tore the anterior cruciate ligament and meniscus in his left knee.
How long did the anterior cruciate ligament and meniscus in his left knee injury keep Henrik Larsson out?
Despite his injury-hit 2004–05 season, playing only 16 games, Barcelona took the option to extend Henrik Larsson's contract.

Question: How long was his contract extended?
Self-contained rewrite: How long was Larsson contract extended?