The Ireland captain was taken off in the second half of the 29-9 win over the Pumas, amid fears of that he had broken or cracked a bone in his jaw.
Speaking immediately after the match, Ireland head coach Declan Kidney said: "We're told he could have a crack in his jaw. If it's just a crack, he might avoid having to have surgery but we won't know until later (in the week)."
Meanwhile, O'Driscoll's Leinster and Ireland team-mate Rob Kearney is facing at least two months on the sidelines after undergoing surgery on the knee injury he picked up against New Zealand.
Young winger Andrew Conway, who scored a try in Leinster's 19-15 defeat to the Ospreys, has been ruled out for three weeks after injurying his neck in last Sunday's game in Swansea.
The Ireland Under-20 international returned home with the remainder of the Leinster squad on Sunday night, and will be bitterly disappointed to be injured after scoring two tries in three appearances for the province this season.
All of the returning Ireland players from the GUINNESS Series are available for selection for Leinster this week after reporting for training on Tuesday morning.
However, it is unlikely that all will feature given the high volume of training and matches in recent weeks.
Nathan Hines' availability is also uncertain as his return to Ireland after playing for Scotland over the November period has been delayed because of the adverse weather.
There are a number of other bumps and bruises as Leinster prepare for their second trip to Wales in five days, though hooker Richardt Strauss and centre/out-half Shaun Berne are back in the mix.
Head coach Joe Schmidt will confirm the team and replacements to play the Scarlets on Thursday afternoon.