Dunbar was on the pitch from start to finish as Glasgow Warriors were beaten at Leinster in their 2012 RaboDirect PRO12 semi-final - and the same again a year later.
Now the competition has thrown up the same fixture on the biggest stage and Dunbar will no doubt have a role to play if the Warriors are to turn the tables.
The 24-year-old centre has enjoyed his best season yet this year, managing just ten RaboDirect PRO12 appearances courtesy of international interruptions.
Since his Scotland debut back in June, Dunbar has been a central figure in Scott Johnson's side - and he will be hoping to carry that role into the Vern Cotter era.
Back in Glasgow he is a key player in Gregor Townsend's Warriors side - a figure of stability outside the club's much-rotated No.10 shirt - and Saturday's clash at the RDS is the big stage for which he has been waiting.
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