After victories over Israel and Moldova, the trip to Austria looked, on paper at least, as if it would be Denmark's toughest test in qualifying for Qatar 2022. That seemed to be the case until a second-half blitz in Vienna saw The Danes net four goals in 15 minutes to take control of Group F.
Andreas Skov Olsen got two of them, either side of efforts from Joakim Maehle and Pierre-Emile Hojbjerg, as Kasper Hjulmand's side took their tally to 14 goals scored, none conceded this week.
Christian came off the bench for the final 13 minutes to earn his fourth cap while Mathias Jensen, who got one of Denmark's eight against Moldova on Sunday, was an unused substitute, keeping him on five appearances for his nation.
Denmark look in rude health ahead of the summer's European Championships where they have been drawn against Finland, Belgium, and Russia in Group B.
The Danes' opening Euro 2020 game is on 12 June in Copenhagen against Finland, for whom Marcus Forss earned his fourth cap last night. The Bees striker played 65 minutes in St Gallen as The Finns were beaten 3-2 by Switzerland in a friendly.
Mario Gavranovic opened the scoring for the hosts after 21 minutes but a quickfire double from Marcus' strike partner Joel Pohjanpalo sent Finland into the break ahead. Rubén Vargas levelled things just before the hour with Haris Seferovic heading home the winner four minutes from time.