After winning the WBO world heavyweight title eliminator, Thompson was appointed the mandatory position in the organization's rankings, thus setting up a bout with then-WBO world heavyweight champion Sultan Ibragimov. The mandatory fight was delayed twice due to a scheduled unification showdown – first between Ibragimov and WBA world champion Ruslan Chagaev, which was ultimately cancelled, then after an agreement was reached between Ibragimov and then-IBF world champion Wladimir Klitschko. Thompson agreed for a stay-busy bout on September 27, 2007 against Cliff Couser, who was coming off of an upset second-round TKO win over Monte Barrett. Thompson defeated Couser by second-round technical knockout. At the conclusion of 2008, Thompson entered "The Ring" heavyweight rankings at No.9 and was ranked No.7 heavyweight by BoxRec.