Thomas Barr runs in the 400m hurdles heats at the National Championships in Santry on Saturday afternoon.

The Dunmore native missed out on an Olympic qualifying standard in recent weeks and now has one roll of dice left in Dublin.

The closing window for qualification is on Sunday night, with Barr needing rankings points to stay within the top 40 in the world.

His heat on Saturday afternoon at 5.25 pm should be routine ahead of the final at lunchtime on Sunday.

Athletics writer Cathal Dennehy joined On The Ball to discuss Barr and his hopes of making it to Paris.