Matt Hardy and Sheamus.
On the June 30 episode of ECW, Sheamus made his debut as a villain, calling himself The Celtic Warrior and defeating a local competitor. Shortly after his debut, Sheamus entered a rivalry with Goldust. Sheamus defeated Goldust on two consecutive editions of ECW before suffering his first loss on the August 13, 2009 episode of WWE Superstars. The feud came to an end on the September 1 episode of ECW when Sheamus was victorious in a No Disqualification match. Following this, he entered a brief feud with Shelton Benjamin.
On the October 26 episode of Raw, Sheamus made his debut for the Raw brand by defeating Jamie Noble. Despite this, he appeared on the October 27 episode of ECW, defeating Benjamin and ending their rivalry.On November 2nd he would face Jamie Noble in which he won due to the referee stopping the match, after the match Sheamus continued the assault on Jamie, which ended after Sheamus powerbombed him to the mats. Jamie would then annouce his retirement on November 10th.Sheamus made his WWE pay-per-view debut at the Survivor Series in an elimination match, eliminating both Finlay and John Morrison from the match, and becoming a survivor along with The Miz and Drew McIntyre. The next night on Raw, Sheamus became the number one contender to the WWE Championship by winning a Breakthrough Battle Royal featuring superstars who've never had a World Title shot before.
On December 13 at TLC: Tables, Ladders & Chairs, Sheamus defeated John Cena in a tables match to win the WWE Championship his first title in the WWE. Upon winning the title, Sheamus became the first Irish-born WWE Champion. The following night on Raw, Sheamus was awarded with the "Breakout Superstar of the Year" award at the 2009 Slammy Awards.