England fly-half Owen Farrell will discover in the coming days the severity of the foot injury that forced him off at half-time of Saracens' 28-24 Aviva Premiership victory over Northampton.
Farrell had to be relieved of his kicking duties by Marcelo Bosch after damaging his right foot at Allianz Park and failed to appear for the second half.
"It's too early to say about Owen. It's a foot injury and you never know with foot injuries," Saracens director of rugby Mark McCall said.
"Owen doesn't remember when it happened. We'll have news later in the week. He couldn't kick with it."
Saracens coasted into a 28-10 lead with tries from David Strettle, Kelly Brown and Bosch, but Saints fought back with a late flurry of points after Luther Burrell and George North crossed in the final 10 minutes.
The nervy finish failed to mask Saracens' domination for most of the match and the Premiership leaders now need just two more points to guarantee a home play-off.
"It was tight at the end but I wouldn't want to ignore the first 70 minutes. We were really good and hard to handle at times," McCall said.
"I was chuffed with how we played and I think that's up there with how well we've played all season.
"What I enjoyed was the intent we had in everything we did. Intent to attack, intent carrying, intent at chasing kicks and intent in defence.
"We'll ignore the last 10 minutes because before that we were brilliant."
Second-placed Northampton are 10 points adrift of Saracens and their lead over Leicester, who occupy third, is only three points.
The loss at Allianz Park was their third successive Premiership defeat, but director of rugby Jim Mallinder denies the run is evidence of a deeper malaise.
"Saracens dominated the game for 70 minutes. We didn't get many opportunities," Mallinder said.
"We're disappointed because the accuracy of our game wasn't quite there, but we showed character to come back.
"We're not playing as well as we did before and during the Six Nations.
"But we're not too concerned because Saracens are a good side and we know we played into their hands a bit."
Mallinder revealed that hooker Dylan Hartley is expected to return from his shoulder injury before the end of the season, while prop Alex Corbisiero's comeback from a knee problem is pencilled in for May 2 against Bath.