Also in 2003, he was fourth official to Graham Barber at the FA Cup final held at Cardiff's Millennium Stadium, where Arsenal beat Southampton 1–0.

[5] Dean made it to the Millennium Stadium eight days later though, when he refereed the Championship play-off final between Leeds United and Watford.

Dean's highest refereeing honour came on 17 May 2008 when he took charge of that year's FA Cup final between Portsmouth and Cardiff City, with Trevor Massey and Martin Yerby as his assistants and Chris Foy as the fourth official.

[12] On 2 April 2019, during a game between Wolverhampton Wanderers and Manchester United at Molineux, Dean issued the 100th red card of his career as a Premier League referee to Manchester United's Ashley Young, making Dean the first referee in Premier League history to reach the 100 red cards milestone.

[16] He also made another cameo appearance as himself in Season 3, Episode 12 of Ted Lasso as the referee in the game between the fictional AFC Richmond and West Ham United.

The controversy surrounds Tottenham's first equaliser by Pierre-Emile Hojbjerg, first on his potential foul on Chelsea's Kai Havertz and subsequently his shot that led to the goal, with Tottenham's Richarlison standing in an offside position and potentially blocking Chelsea's Edouard Mendy line of vision.

The other was Tottenham's Cristian Romero's hair pull on Chelsea's Marc Cucurella at the final moments of the game, a disallowed action that was reviewed by Dean as not being a foul, leading to Spurs' late equaliser by Harry Kane in the subsequent corner.

Two days later on 18 August, Dean personally admitted his mistake in regards to the incident, adding that he should have asked Anthony Taylor, the referee during the fixture, to review the hair pull on the pitch-side monitor instead of carrying on.

Dean's next European Championship match was on 12 October 2010 when he oversaw a group A qualifier for Euro 2012 between Belgium and Austria in Brussels.

The away team appeared to have secured a 3–2 victory but two Belgium goals on 87 and 89 minutes overturned that scoreline, only for ten-man Austria to score an injury-time equaliser to earn a 4–4 draw.