The next day, he made his first team debut in a 2–1 League One defeat to Huddersfield Town at The New Den, replacing Danny Spiller for the final eight minutes. He scored his first goal in a 3–2 loss to Swansea City in the first round of the Southern Section of the Football League Trophy on 4 September, and his first league goal in a 2–1 defeat to Swindon Town on 29 September. His performance saw him earned November's PFA Fans Player of Month award for League One. On 15 December, he was sent off for celebrating in the crowd after equalising in a 2–3 home loss to Oldham Athletic. His loan was due to expire on 1 January 2008, but was later extended to the end of the season. Simpson scored eight goals in 44 appearances for Millwall and won the PFA Fans' League One player of the year award for 2008. Simpson thanked Millwall for giving him the chance to improve his game, stating "Going to Millwall was the best decision I have ever made. Playing regularly in the first team really developed my game. It helped me grow as a player and I made a lot of good friends. It did me the world of good. The Millwall fans were really good to me – and I appreciated their support." He signed a new contract with Arsenal on 29 December 2008, but was then loaned out to West Bromwich Albion for the remainder of the 2008–09 season. He made his Albion debut on 3 January 2009, coming on as a half-time substitute for Robert Koren in a 1–1 draw with Peterborough United at The Hawthorns in the FA Cup third round. He scored his first goal for the team ten days later, in a 2–0 win in the replay. His first Premier League goal was scored on 31 January, in the 2–2 draw against Hull City at the KC Stadium. After making seventeen appearances and scoring two times in all competitions, the club were relegated back to the Championship after one season in the Premier League. Following this, Simpson returned to his parent club. On 27 August 2009, Simpson joined the Championship's Queens Park Rangers on a season-long loan. He made his debut in a 1–0 away win at Scunthorpe United. His third game for QPR was against Cardiff City, at the Cardiff City Stadium, and he