|Irish name||Brian Mac Coisteala|
Abbeyknockmoy, County Galway, Ireland
Costello has played inter-county hurling with Galway's minor, under-21, intermediate and senior teams, having captained the intermediate team in 2008 and was a member of the senior panel in 2009. Costello emigrated to London in 2011 where he linked up with the London senior hurling team. As an inter-county hurler he has won one under-21 all Ireland, one Christy Ring Cup winners' medal and one Nicky Rackard Cup winners' medal.
In 2012 Costello was named the Christy Ring Hurler of the Year in addition to being awarded a GPA All-Star for his contribution to the London Christy Ring winning team.