Saracens' Mark McCall awaits injury news on Vunipola brothers and Maro Itoje

Mark McCall was left counting the cost of Saracens' bruising Round 1 battle with Glasgow at Scotstoun Stadium.

The Londoners opened their Heineken Champions Cup campaign with a 13-3 victory in Glasgow - but it was a match that left its mark on some of the team's top stars.

Mako Vunipola and brother Billy both had to be replaced with knocks while their England team-mates Maro Itoje and Jamie George were also in the wars with broken noses.

That could present Eddie Jones with a headache as he prepares to name his England squad for the Quilter internationals, that will be live on Sky Sports, on Thursday.

But Saracens' director of rugby McCall's concern is now about how many of his main talents he will have to call on for next Saturday's visit of Lyon.

"Mako's is a calf injury, Billy's an arm - but it's too early to say how serious they are," said the director of rugby after the full-time whistle.

"Owen Farrell got a bang on his knee but he seemed to be OK after the game. Nick Isiekwe hurt his calf or his ankle too and that's why he wasn't able to continue on the field.

"Maro and Jamie have both got broken noses - so it was a tough old game. It's a bit of a worry for next weekend the amount of injuries we've picked up

"Is that an unusual injury toll? Of course it is. But it is the way it is."

Regarding the match itself, McCall said it was a "very important" win for his side, even though he admits they were not on top form.

"I don't think it was our best performance - pretty far from it - but all of that is down to the opposition we're playing against," noted the director of rugby.

"It's a very important win and the most pleasing thing is how we scrapped when we needed to scrap.

"I thought Glasgow defended brilliantly. They made us work really hard for quick ball, something we struggled to get. They are a dangerous team as well and we had to scramble back a few times."

Glasgow coach Dave Rennie reflected on the match and said that they would look at his own side's faults above anything else.

"We gave them a pretty soft 10 points early on in the game," said the New Zealander. "From then on I thought we defended pretty well.

"Can't fault the attitude - the effort was outstanding. But we just need to be far more clinical and patient when we're attacking, especially on the penalty advantage. You can go seven, eight or nine phases, keep applying pressure, but a couple of times we've gone for the miracle play.

"If we start talking about refs we'll be here for a long time. There was obviously a couple of decisions that could have gone the other way, maybe, but we'll look at ourselves. We just need to be more clinical with ball in hand and turn.