You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "when did lionel messi started playing for barcelona?" whose answer is 2001.
Each document should contain about 30 words, and these documents should contain useful information.

Query: when did lionel messi start playing for barcelona
Useful Output:

Doc 1: The Early Years (2004-2008) In La Masia and the Barcelona B team, Lionel Messi played mostly on the left wing or as a number 10. Messi said…
Doc 2: Lionel Messi, an FC Barcelona youth product, was promoted to the senior team during the 2004-05 season and he made his La Liga debut for the
Doc 3: It made Messi the youngest player to represent Barcelona in a senior professional match, aged just 17 years, three months and 22 days old. In May of that season
Doc 4: November 16, 2003. A date to remember, as one of the most important historical milestones in Barça history took place.
Doc 5: Messi's competitive debut for Barcelona did not come until 16 October, 2004, when he was a substitute against Espanyol. He played only eight