He joined Ulster in 2008 from Leicester Tigers having previously played for Ulster at under 21 level where he captained them during the 2002/03 season and has also represented Ireland at U19, U21 and 'A' level, and captained the Irish side at the Rugby World Cup Sevens tournament in Hong Kong in March 2005.

During October 2006 Humphreys was loaned out to first division Leeds where he made 4 appearances, scoring 2 tries and a drop goal.

After more assured performances, and a hamstring injury to Andy Goode, Humphreys was selected to play Munster at Thomond Park in a decisive Heineken Cup pool game.

[2] After his brilliant performance in a high tempo match he was the selected for his Ireland A début against England Saxons at Ravenhill, in his native Ulster.

In April 2008, after falling out of favour at Leicester, Humphreys signed for Ulster to replace his retiring brother.