Boss Jim Mallinder admitted the triple first-half injury blow hindered Saints’ chances in their 16-6 defeat to Saracens.
But the director of rugby was pleased with the way his team reacted to losing three influential players.
Mallinder was forced to replace England duo Courtney Lawes and Dylan Hartley along with third choice full-back and first choice kicker Stephen Myler.
It meant Saints had to play the full second half without any of the trio in the side and Saracens shut the door to record a fine win at Franklin’s Gardens.
The home team failed to register a try during the game, failing to find the spark needed to get over the try line.
And Mallinder said: “It doesn’t help when you’ve got two key England lads plus Stephen Myler at full-back going off with injuries.
“That doesn’t help but, having said that, I thought we played well in the first half. It was into a big gale, we played some good rugby.
“It was of course disappointing to concede that try when we were in attack, they turned it over and scored a cracking counter-attack.
“We were probably unlucky to turn round in that deficit and I was confident about the second half.”
Alex Goode’s first-half score, allied with 11 points from the boot of Owen Farrell got the job done for Saracens and saw Saints knocked off the top of the Aviva Premiership.
They were set to lose their England contingent to international duty on Monday anyway, but it is now uncertain just how long Lawes and Hartley will be missing for Saints.
“Both knee injuries, both unable to carry on,” said Mallinder when quizzed about the nature of the knocks. “Both have done something and we’ll find out later.
“Lawes and Hartley are characters that if they had just got a knock and they were going to be running around on Monday, they wouldn’t have come off.
“It was disappointing they had to go off.”