He is also known for his work in Total Nonstop Action Wrestling (TNA) under the ring name Rudy Charles, where he was the promotion's senior referee.

Engler joined Total Nonstop Action Wrestling (TNA) shortly after its inception in June 2002, and was quickly named senior referee.

This was all short lived as Booker hit Charles with an Axe Kick, finished off Thomas with the Bookend for the pin, and forced Earl Hebner to make the count.

On his debut in National Wrestling Alliance Main Event, Shawn Shultz lost his NWA Mid-America Heavyweight Championship.

On the March 14, 2016 episode of Raw, Engler was injured after being hit in the leg with a production crate by Triple H during a backstage brawl between him and a returning Roman Reigns.