On September 9, 2008, Hager made his start on the ECW brand under the ring name Jack Swagger, winning a match against a local wrestler. He quickly made himself a villain when he did not let the referee hold up his arm after the win, and later started a rivalry with Tommy Dreamer by attacking him after Dreamer had saved Chase Stevens from Mike Knox. He later defeated Dreamer in a wrestling match and an "All American Challenge" competition. After weeks of fighting, the two ended their rivalry in an Extreme Rules match, which Swagger won to extend his undefeated streak. He then set his sights on Matt Hardy's ECW Championship, and was named the number one contender on the December 30, 2008 edition of "ECW". On the January 13, 2009 episode of "ECW", Swagger defeated Hardy to win the ECW Championship, which is his first title in WWE. His undefeated streak in singles matches ended on the February 3 episode of "ECW", when he lost to Finlay.