Most victories in a football European club competition (single season)

According to Official Guinness Records,

The most victories in a single season of a football European club competition was 15 by F.C. Porto in winning the 2011 UEFA Europa League championship. It marked Porto's second-ever UEFA Cup victory.
"Os Dragões" bested the previous mark of 13 held by Barcelona in 2002-03.

For a complete list of 2011 records, please visit 2011 Guinness Records in Portugal.

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