Mark McCall welcomed the "extraordinary" comeback made by Billy Vunipola as Saracens swept aside Wasps 38-15 in an Aviva Premiership victory at the Ricoh Arena.
Vunipola was a force throughout the 69 minutes he was on the pitch with his ball-carrying contributing to some of the European champions' finest moments in a bonus-point win.
The 25-year-old No. 8 was making his first appearance for 15 weeks after recovering from knee surgery, his third major operation in 10 months.
In a further Six Nations boost for England, Maro Itoje returned from a month out with a fractured jaw and, while less conspicuous than the marauding Vunipola, he came through unscathed.
"Having Billy back makes a difference to any team," Saracens director of rugby McCall said.
"It's extraordinary in some respects to play as well as he did, given that he hasn't played for four months.
"You could see how motivated he was, the fight that he had. He gets you over the gain-line when others wouldn't sometimes.
"I thought he was brilliant and hopefully that game-time will make him all the better for next week.
"The history with Billy is that he comes back well and comes back with a performance like that, but you just don't know how long it will last because a game is so different from training.
"He hasn't done that many training sessions, but it's not really a surprise.
"He understands that he needs to bring control to his performance as well as all the aggression he showed on the ball. He had the balance just right here."
Saracens put further distance between themselves and the seven-match losing run that ended last month by cutting Exeter's lead at the summit of the table to five points with a hugely impressive triumph.
"We've had some good performances and there have been some games where we've played really well," McCall said.
"We've now got ourselves into a decent position in the league, which is good. We've had two away games against Leicester and Wasps and won, so we've come out of this period well."