Pat Lam praised Bristol’s battling qualities after seeing them move second in the Gallagher Premiership.
George was also yellow-carded, and Bristol held on to clinch the win following a largely forgettable contest that saw more than 30 penalties awarded.
“I am extremely pleased,” Bristol boss Lam said.
“It wasn’t beautiful weather, but if we want to be where we are going, you have to get excited by playing how you have to play.
“Things like the weather were in Saracens’ favour with the pack they had picked, and we didn’t have as much time on the ball.
“But our defence and our scrummaging were huge. Credit to our coaches for that.
“The boys gutsed it out. We hung on in there in the end.
“Good teams when they need to defend, they defend. Everyone knows us for our attack – but we want to get our defence right, too.”
Bristol also had to survive a late Saracens onslaught following their replacement prop Max Lahiff’s sin-binning.
But they prevailed courtesy of three Callum Sheedy penalties and the seven-point penalty try, denying Saracens a 10th Premiership win before their relegation to the Championship next term.
Saracens rugby director Mark McCall admitted a sense of frustration after seeing his team come unstuck.
“It is always frustrating to come out the wrong side,” McCall said.
“But it was a game that could have gone either way. Our attitude was good, out physicality and energy was good.
“But our set-piece wasn’t good enough and we had countless chances five metres from their line.”
England star Farrell, meanwhile, could be in the mix for next Saturday’s Premiership appointment with Harlequins.
Farrell sat out the Bristol encounter due to a thigh issue, but McCall added: “It’s a very minor strain, so there is a good chance he will play next week.”
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