Diego Sanchez will get a stern test in his first fight at 155 pounds.

The middleweight winner of the first season of Spike TV’s “The Ultimate Fighter” has signed a bout agreement to face Joe Stevenson at UFC 95 on Feb. 21 at the O2 Arena in London, according to a source close to the New Mexico native. Stevenson was expected to follow suit.

Sanchez, 26, announced his intentions to drop down to the lightweight division in December and will enter his first fight of 2009 on a two-fight win streak. Sanchez (19-2) submitted David Bielkheden at UFC 82 last March and stopped gritty American Top Team standout Luigi Fioravanti with strikes at “The Ultimate Fighter 7” Finale in June.

Sanchez’s only two career losses have come in the welterweight ranks to Josh Koscheck at UFC 69 in April 2007 and Jon Fitch via split decision at UFC 76 in September 2007, shortly after he left lifelong trainer Greg Jackson in Albuquerque, N. M. Sanchez now trains under Brazilian jiu-jitsu black belt Saulo Ribeiro and Rob Garcia in San Diego.

Stevenson (29-9), who won TUF’s second season at welterweight, has dropped two of his last three bouts. The former King of the Cage and Gladiator Challenge champion succumbed to a second-round rear-naked choke at the hands of lightweight champion B.J. Penn at UFC 80 last January in Newcastle, England, and was submitted with the same maneuver by Kenny Florian at UFC 91 in November. The 26-year-old ground fighter has gone 6-3 in the Octagon.

This article was updated at 2:03 p.m. EST on Dec. 20, with additional information from a source close to Diego Sanchez.