Making his first-class debut for the county in the 2002 County Championship against Kent, Pothas followed his up by making his List A debut in the same season against Kent in the 2002 Benson and Hedges Cup and the following season he played in Hampshire's first ever Twenty20 match against Sussex. A regular in all formats for Hampshire, he has played to date 124 first-class matches for the county, scoring over 7,000 runs and taking 355 catches behind the stumps, making him one of Hampshire's most successful wicket-keeper batsman. Up to the 2010 County Championship, Pothas had scored over 800 first-class runs in every season with Hampshire, besides the 2002 and 2007 seasons. Injury put paid to him recording over 800 first-class runs in the 2010 County Championship. Since making his debut for Hampshire, he has been at the forefront of one of the county's most successful periods, winning the 2005 Cheltenham & Gloucester Trophy and 2009 Friends Provident Trophy, in the final at Lords he made 35 runs from only 31 balls, including a huge six in to the Tavern Stand, in a winning partnership worth 67 runs with Chris Benham, who hit the winning runs. In the field Pothas caught his opposing wicket-keeper Matt Prior for a duck, and caught Pakistani international Yasir Arafat behind for 9. He was also a runner-up for the Hampshire in the 2005 County Championship and the 2007 Friends Provident Trophy. It was in 2007 that Pothas became eligible to be selected for England, four years after receiving his Hampshire cap.