Hien had to settle for a 10-minute league debut in the 1-1 match against Juventus a week ago, but was back in the starting lineup against Napoli (2-3) four days later. Against Sturm Graz in the Champions League, he played again from the start as a central defender in a three-man defense.
In Bergamo, Atalanta took command directly. The away defense couldn't get the ball out of their own penalty area - a blunder that cost an early goal.
Davide Zappacosta combined with Mateo Retegui - 17 goals this season - who pushed the ball in to make it 1-0 for Atalanta after just 13 minutes. After the break, it was a landslide - Mario Pasalic, Charles De Ketelaere, Ademola Lookman, and Marco Brescianini increased the score to 5-0.
Atalanta has 14 points and will at least enter the round of 16 as one of the 24 highest-placed teams.
After seven matches, the Italian Serie A club has only lost one match and conceded just four goals. The group stage concludes next week away against Barcelona.
Monaco spiced up the battle for the eight top spots - which entail play in the quarterfinals - by beating Aston Villa at home. Wilfried Singo nodded in the only goal of the match early on.
With one match left to play in the group stage, both clubs are on 13 points.
National team goalkeeper Robin Olsen sat on Aston Villa's bench.
