Nafti was signed on loan by Birmingham City in the final minutes of the January 2005 transfer window, making his Premier League debut on 5 February in a 2–0 loss away to Manchester United in which he started and was booked. Sometimes referred to as "Nasty" due to his fiery nature and tendency for cautions, he was primarily signed to replace the outgoing Robbie Savage, and finished the season strongly, which led to a permanent deal being agreed in the summer.