UPDATED 05:22 1st June 2015
Ryan, 27, is a 6ft 2in striker who began his career at home-town club Rotherham United, making over 100 appearances and scoring twice in the 2010 play-off final at Wembley. He then joined Bristol City in 2011 for an undisclosed fee. In January 2014 he moved to Portsmouth, scoring ten times for Pompey last season in his 41 appearances. He signed for Oxford in May 2015 on a two-year deal.