Mark McCall's Saracens survived an injury scare ahead of their upcoming April 5 Heineken Cup quarter-final against Ulster.
They also played in front of a new attendance record for a club match of 83,889 in their 39-17 victory over Harlequins at Wembley to stay top of the Aviva Premiership.
Former Ulster coach and Saracens director of rugby McCall later questioned why a dangerous tackle on David Strettle was not referred to the television match official.
Strettle was carried off on a stretcher in the sixth minute after a swinging arm from number eight Maurie Fa'asavalu knocked him out amid a physical start to the Wembley showdown.
Referee Tim Wigglesworth failed to consult the TMO even though Strettle received treatment for several minutes.
Replays of the incident were damming, but McCall refused to condemn Fa'asavalu.
"I didn't see the angle everyone is talking about, so I can't comment on it," McCall said.
"It would be foolish for me to say anything. David is OK. He's pretty shaken up but he's OK.
"The Richard Wigglesworth penalty which the referee came back for was something out of nothing compared to what happened to David.
"There is a system that can be used by the officials in this situation. Clearly it wasn't used as well as it could have been. In all matches a couple of things go on that probably shouldn't."
The tackle is sure to interest the citing officer, but Quins director of rugby Conor O'Shea backed Fa'asavalu. He said: "There should be nothing on that. I've seen it."
Owen Farrell, Chris Ashton, George Kruis, Jacques Burger and Marcelo Bosch scored tries as Saracens reclaimed top spot in the Premiership, aided by Northampton's defeat at Sale.
But it was a far from thrilling spectacle as Quins were a distant second best. "To have a record crowd for a run of the mill Premiership game was brilliant," O'Shea added.