Career
Early career
Tomlin started his career with the youth system of Leicester City in 1998 before joining Rushden & Diamonds"s youth system in 2005. In October 2005, he became Rushden"s youngest ever player when he came on as a substitute for Drewe Broughton in the 74th minute. He made 21 appearances in League Two in the 2005-2006 season.
Before the 2006-2007 season, Tomlin attracted the attention of several big clubs and he earned a trial with Liverpool.
Throughout the season, he made more starts and became more of a regular in the Rushden starting eleven. He scored his first goal for the club against Weymouth, the match after Paul Hart was sacked, in the 21st minute.
He scored six goals during the season, playing as a forward and on both wings. Following the end of the season a six-figure bid for Tomlin was rejected from another Blue Square Bet Premier club believed to be Crawley Town and Rushden confirmed he would be offered a new contract.
Peterborough United
Tomlin signed for League One team Peterborough United for an undisclosed fee on 6 August 2010.
On 10 December 2011 he scored a diving header against Leicester City at the King Power Stadium to rescue a point, the game ended 1–1. Tomlin beat five defenders to score in Peterborough"s last game of the 2012-2013 season, away to Crystal Palace, but the 3–2 defeat confirmed their relegation back to League One. Middlesbrough
On 31 January 2014, Tomlin signed for Middlesbrough on loan for the remainder of the 2013-2014 season with a view to a permanent move.
On 18 February, it was announced that he had signed a permanent deal on a three-and-a-half-year contract.
Tomlin made his debut on 22 February in a 0–0 draw against Leeds United, coming on as a substitute for Kei Kamara. Bournemouth
On 4 August 2015, Tomlin signed for Premier League newcomers Bournemouth on a three-year deal for a fee around £3.5 million.