The 23-year-old Swiss-born Portuguese Under-21 internationalist has been recruited by Craig Levein in the wake of an unconvincing start to the season from current No.1 Zdenek Zlamal.
The Czech had a particularly shaky display in last weekend’s home draw with Ross County and is at risk of losing his place to the highly-regarded Pereira.
The new recruit, who played in two pre-season matches for United in Australia last month, insists he is ready to be pitched into battle at Fir Park on Friday.
“I’m fitter than ever,” he told Hearts TV. “I knew that I was going on loan so I knew had to be sharp and be ready for whatever was coming up. I didn’t know when I was going on loan but I knew I had to be ready to get started. Now I’m here, I’m fitter than ever and I’m hungry for more. I can’t wait to get started.”
Pereira joined United as a teenager from Swiss club Neuchâtel Xamax in 2012 but, as an understudy to the likes of David De Gea and Sergio Romero, he has been restricted to just three competitive appearances for the Old Trafford club – all of them coming in 2017. He has spent time on loan in Portugal and Belgium in recent seasons and amassed 16 caps for Portugal Under-21s.
In addition to Pereira and Zlamal, Hearts also have the possibility of calling on Colin Doyle for Friday’s match in Lanarkshire. The Irish internationalist last week signed a new contract, but it is unlikely he will be restored to the team at a venue where he made a calamitous mistake back in February.