UFC Fight Night: Shields vs. Ellenberger (also known as UFC Fight Night 25 or UFC Fight Night: Battle on the Bayou) was a mixed martial arts event held by the Ultimate Fighting Championship on September 17, 2011 at the Ernest N. Morial Convention Center in New Orleans, Louisiana.

The event was the last UFC Fight Night aired on Spike, and in general, the last UFC Fight Night labeled event until the debut of Fox Sports 1 in 2013.

Mackens Semerzier was expected to face Mike Lullo at the event,[3] but pulled out of the event on August 31[4] and was replaced by Robbie Peralta[5] DaMarques Johnson was expected to face Clay Harvison at the event,[6] but pulled out of the bout with an injury on August 31 and was replaced by Seth Baczynski.

[7] Daniel Roberts was originally scheduled to face TJ Waldburger, but pulled out due to an injury and was replaced by Mike Stumpf.

[8] The entire preliminary card was streamed on Facebook.