Mako and Billy Vunipola injuries of great concern for England ahead of autumn internationals

To make matters worse for England coach Eddie Jones, Owen Farrell and Nick Isiekwe picked up knocks while Jamie George and Maro Itoje both suffered broken noses

Mako Vunipola (left) and brother Billy (centre) both suffered injuries in Saracens' win over Glasgow Warriors (Getty)

England are sweating on the fitness of influential brothers Mako and Billy Vunipola after they were both forced off with injury during Saracens’ 13-3 victory over Glasgow Warriors in the Heinken Champions Cup on Sunday.

Mako Vunipola, England’s first-choice loosehead prop and last season’s player of the year, was seen in a protective boot on his left foot, while younger brother Billy – who has suffered a horrendous run of luck over the last 18 months with shoulder, knee and arms injuries – limped off with a sore knee and also had ice on the arm that he broke twice earlier this year.

To add to England head coach Eddie Jones’ concerns, both Jamie George and Maro Itoje suffered broken noses while Owen Farrell picked up a knock and forward Nick Isiekwe was forced off injured, and with the Australian set to announce his autumn international squad on Thursday, there are major concerns over key members of the England squad.

"Mako's is a calf injury, Billy's an arm - but it's too early to say how serious they are,” said Saracens director of rugby Mark McCall.

"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."

England will be left sweating on the fitness of the influential brothers (Getty)

Regarding the victory itself, which Saracens clinched courtesy of a Michael Rhodes try and eight points from Farrell’s boot, McCall said it was a "very important" win for his side, even though he admits they were not on top form.

He said: "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.

"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."

Billy Vunipola left the field with an arm injury (Getty)

The one positive England-wise came in Rhodes’ performance, with the South African-born flanker expected to be named in Jones’ squad come Thursday morning after qualifying for England on residency grounds.

Warriors had reason to be frustrated with French referee Mathieu Raynal after he failed to spot Alex Lozowski being dragged into touch in the build-up to Rhodes' try, as well as allowing Saracens to drag down a series of mauls in first-half stoppage time without being pinged for a penalty try.

Jamie George suffered a broken nose during the victory (Getty)

But Glasgow coach Dave Rennie said he would look at his own side's faults before taking aim at the officials.

"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 pressure into points."

Additional reporting by PA