On December 19, 2006, ESPN announced the purchase of a minority stake in the AFL. This deal included television rights for the ESPN family of networks. ESPN would televise a minimum of 17 regular season games, most on Monday nights, and nine playoff games, including ArenaBowl XXI on <answer>ABC</answer>. The deal resulted in added exposure on ESPN's SportsCenter. However, after the original AFL filed for bankruptcy, this arrangement did not carry over to the new AFL, which is a separate legal entity.
What network broadcast ArenaBowl XXI?
ABC