On Thursday the club announced the signings of full-back Amorosino and flanker Doyle on three-month contracts and the pair will link-up with the squad this week.
Foley told Munster's official website: "With the injuries that occurred within the squad, we needed to bring in quality players from overseas that can play with us for a period.
"We would previously have had to announce 38 players in a European squad and this year we've had to announce 41. We already had five academy players in the squad and in order to balance that up, with the likes of Peter O'Mahony and Felix Jones missing out, we needed to look elsewhere.
"Fortunately enough we found Lucas and Sean. It's hard during this period, within a six-day timeframe, to get players of quality, and a lot of hard work was done in the background through Garrett Fitzgerald (Munster's CEO), Niall O'Donovan (the team manager) and all the coaches to get players of a standard where we can be competitive on both fronts."
Amorosino can play at full-back and on the wing and has 49 caps for Argentina, having featured in five of their matches at this year's World Cup.
The 30-year-old made nine appearances in the GUINNESS PRO12 for Cardiff Blues last season and includes Leicester Tigers and Montpellier among his former clubs.
Doyle is another with GUINNESS PRO12 experience, having spent two seasons at Ulster, and joins from Super Rugby side the Brumbies.
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