After the club failed to gain promotion, Roberts handed in a transfer request and was sold to West Bromwich Albion in July 2000. His goals helped the team reach the First Division play-offs in his first season at the club. West Brom then won promotion to the Premier League in the following season. Roberts scored three goals in his first Premier League season as the club were relegated back down to the First Division. He was loaned out to Portsmouth at the start of the 2003–04 season, and was then sold to Wigan Athletic in January 2004. Roberts went on to score 21 goals in Wigan's promotion-winning campaign in the 2004–05 season, and won the club's Player of the Year award at the end of the season. His goals in the following season helped the club finish tenth in its inaugural Premier League campaign, as well as taking the team to the 2006 Football League Cup Final at the Millennium Stadium – the club's first ever major cup final.