Beirne said that Argentina “came out firing” in Dublin as they chased a first away win over Ireland, something that came as no surprise to the Irish pack.
“We weathered the storm and got into how we wanted to play the game,” said Beirne.
“What was pleasing about that was some of those tries were proper team tries and everyone was involved with them. That was the biggest takeaway from the game that.”
But, like Farrell, the second row believes there is more to come at the attacking end of the pitch.
“We probably came away a little bit frustrated because we felt we didn’t capitalise on a lot of the territory at the end of the game and the chances we had.
“That shows how good a performance it was to come away feeling like that.”
After a bruising opener, Farrell will be forced to assess his squad ahead of Fiji’s visit to Dublin on 14 November.
After that, world champions South Africa will be a stern test before the finals weekend in London to round out the international window.
He had offered Craig Casey a chance to impress at scrum-half as first-choice Jamison Gibson-Park returns to full fitness, and he impressed after a slow start.
Ulster back row Nick Timoney also put in a big performance, while Prendergast’s showing at fly-half was also largely positive as he put his stamp on the 10 jersey.
When asked if the performances gave him food for thought for selections for the rest of the window, Farrell said: “Definitely, 100%.
“That’s exactly what you are after going into next week.
“Having some good competition, we’ve had it for 10 days in training so how they performed highlights how they have been training.
“Whatever side we pick next week, they’ll be competing to play the following week.”
