The Boca Juniors team bus could be seen driving down the highway towards Buenos Aires after the team landed at Ezeiza International Airport on Monday.
The bus was accompanied by a heavy police escort, with armed officers in cars and mounted on motorbikes.
It comes after Boca lost 5-3 on aggregate to River in Madrid on Sunday.
Boca's Dario Benedetto scored in the 44th minute; however, River did not lose their spirit, with Lucas Pratto equalising in the second half, forcing the match into extra-time.
In the 108th minute, Juan Fernando Quintero scored River's second before Gonzalo Martinez made it 3-1 in the final seconds of the game.
The second match of South America's most important club competition was originally meant to take place in River's home stadium El Monumental; however, it was rescheduled and moved to Madrid due to attacks on Boca's team bus by rival fans upon its arrival at the stadium.