In the opening set , Costamagna had been down 5 - 3 .
In the opening set , Costamagna facing two set points , but rallied back for a 7 - 6 win in a first - set tiebreak .
In the opening set , Costamagna had been down 5 - 3 and facing two set points , but rallied back for a 7 - 6 win in a first - set tiebreak .