A knee injury in 2001 meant that Lumb played only a small part in Yorkshire's success in winning the County Championship that year, although he did record a maiden first-class hundred against Leicestershire.

Lumb made progress in 2002 by becoming a regular member of both the championship and limited-overs sides and, in 2003, scored close to a thousand first-class runs at an average of over 40, including two centuries and six fifties.

He was selected for the ECB National Academy squad the following winter, but failed to kick on as people expected and was dropped by Yorkshire during the 2005 season.

[1] In July 2009, some good form for Hampshire, particularly when opening the batting in the One-Day and Twenty20 games, led for his inclusion in the England Cricket Team's provisional 30-man squad for the 2009 ICC Champions Trophy taking place in South Africa during September 2009.

Lumb made his highest first-class score against Nottinghamshire during a 2009 County Championship game, making 219 runs in Hampshire's first innings.

Lumb was signed by former Hampshire teammate Shane Warne to play for the Rajasthan Royals in the 2010 Indian Premier League, in a deal worth a reported £30,000.

Lumb ended on a high note by collecting a winners medal, as England defeated Australia by seven wickets to win the tournament.