Lewis Macleod came through 75 minutes as Brentford's impressive B team continued a fine run of form in Italy as Inter Milan were left well beaten.
The Scot, who joined from Rangers in January 2015, has been out of competitive action for 12 months after suffering an anterior cruciate ligament injury in the 2-0 win at QPR.
However, he and Sergi Canos, who made a return from an ankle injury, came through three quarters of the game against the Italian giants, following up a victory over AC Milan at the weekend.
The Bees young stars needed just five minutes to open the scoring through Justin Shaibu.
After surviving a brief scare, Canos doubled the lead midway through the first half after being played in by the young Dane.
And, with four minutes of the first half remaining, former Celtic man Theo Archibald, made it 3-0 after Canos and Shaibu combined.
Inter came back into the game in the second half, reducing the arrears after Jarvis Edobor was penalised in the penalty area.
But Brentford came closest to restoring their three goal cushion as Bradley Clayton had a goal disallowed for offside.