Saracens could welcome back Owen Farrell for their Champions Cup semi-final clash with Clermont in a fortnight.
The Premiership side were the only away winners in the quarter-finals, edging out Racing-Métro 12-11 on Sunday to reach a third successive semi-final.
There they will meet Clermont in a repeat of last season's last four clash, which Sarries won 46-6.
That hammering took place at Twickenham however, while this year Saracens will have to travel to Saint Etienne to take on a Clermont side fresh from a crushing 37-5 win over Northampton.
They should have centre Brad Barritt back after he missed the game against Racing, while Farrell could also return after a lengthy absence with a knee injury he suffered against Clermont in the pool stages.
"We have some pretty tough fixtures coming up – Leicester next Saturday is a massive game for us and after Clermont we have Northampton in the Premiership," said McCall, who was grateful that the semi-final will be played away from Clermont's Stade Marcel Michelin, where they have not lost in Europe for seven years.
"We have some players coming back and will have to spread the load during this period. Brad should be back for the Champions Cup semi-final, Owen is touch and go."
"Given Clermont's home record, it's bit of a relief to be playing them on neutral territory. We're still going to France, but it's not quite the same as going to their own ground."