Constable had a run of scoring five goals in as many matches from 28 December 2008 to 20 January 2009, which constituted four home victories for Oxford. Following this, he went seven matches without a goal, before scoring two in a 3–3 draw with Forest Green Rovers on 7 March 2009. Oxford announced he had agreed a permanent contract with the club in April 2009, although this was denied by Shrewsbury, who stated the transfer was not yet complete. He scored the winning goal for Oxford in a 1–0 victory over Wrexham on 11 April 2009 with a header in the fourth minute of stoppage time, which was described as "one of the most dramatic late goals in Oxford United's history". He finished the season with 49 appearances and 26 goals, after which he claimed Oxford's Supporters' Player of the Year and the Players' Player of the Year awards. Constable's permanent transfer to Oxford eventually took place on 28 April 2009, signing a three-year contract for an undisclosed fee. After the end of the season, he won the Conference Premier's Player of the Year and Fans' Player of the Year awards.