Conversation so far:
Did 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.
What happened when the contract was over?
Larsson's contribution in Barca's La Liga win in his first season there was disrupted by serious injury.
What was the injury?
Larsson tore the anterior cruciate ligament (ACL) and meniscus in his left knee.
How long did the injury keep him out?
Despite his injury-hit 2004-05 season, playing only 16 games, Barcelona took the option to extend his contract.

Question: How long was his contract extended?
Self-contained rewrite: How long was Larrson's contract to Barcelona extended?