Sky Media currently manages ad sales for the ESPN and ESPN Classic channels in the UK.
Now, it will also handle sales for the broadcaster's Commercial channel, which is currently available to about 40,000 commercial subscribers in the UK via the Sky pub feed.
The deal takes immediate effect and will run until July 2011.
ESPN Commercial broadcasts a selection of British, European and international sports, including England's Barclays Premier League, Scotland's Clydesdale Bank Premier League, the UEFA Europa League and Italian Serie A.
Jeremy Tester, communications director for Sky Media, said the Sky Sports dedicated pub feed offered advertisers "a unique opportunity to directly target a valuable audience of predominantly young males". He added: "The addition of ESPN Commercial strengthens that proposition."