Benetton Treviso duo Manuel Dallan and Gonzalo Canale have also been drafted in at centre and winger respectively with Matteo Barbini and Mirco Bergamasco the men to make way.
Masi impressed in the opening game against England but missed out in the 25-0 defeat to France because of injury.
He will still need to pass a late fitness test but Kirwan is hoping that will just be a formality.
"I have put Andrea Masi in the first XV even if he hasn't trained at 100% because of injury and he will undergo one more test," Kirwan said on www.federugby.it.
Kirwan also has a couple of other injury concerns ahead of the match at Rome's Stadio Flaminio.
"Sergio (Parisse) is still suffering from a muscle problem and this Friday he will have a test to determine his condition," he said.
"Gonzalo Canale has trained and he appears to be at 100% so he can play against the Scots. Aaron Persico also picked up a minor knee injury in training but I am not worried about it," Kirwan added.
A Masi (Arix Viadana); G Canale (Benetton Treviso), C Stoica (Montpellier), M Dallan (Benetton Treviso), D Dallan (Benetton Treviso); R De Marigny (Overmach Rugby Parma), P Griffen (Ghial Calvisano); A Lo Cicero (Lazio & Primavera), F Ongaro (Benetton Treviso), M Castrogiovanni (Ghial Calvisano), S Dellape (Benetton Treviso), M Bortolami (Safilo Petrarca Padova), A De Rossi (Capt, Ghial Calvisano), A Persico (Leeds Tykes), S Parisse (Benetton Treviso).
C Festuccia (SKG Gran Parma), S Perugini (Ghial Calvisano), C Checchinato (Benetton Treviso), S Orlando (Benetton Treviso), S Picone (Benetton Treviso), R Wakarua (ADMO Leonessa Brescia), N Mazzucato (Ghial Calvisano)