A Louis Picamoles score and one from Tom Kessell, allied with 13 points from the boot of Stephen Myler, earned a 23-20 victory.
It was just Saints’ third in the Aviva Premiership, while Gloucester have now won only one of their seven league matches.
And Mallinder breathed a sigh of relief after seeing his team hold out to earn a win that ensured they bounced back from last Saturday’s 41-7 thrashing at Castres.
“It’s been another interesting week and an interesting 80 minutes,” Mallinder said.
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“It was two nervy sides, the standard wasn’t brilliant, a few good bits, a few bits that weren’t too good, but we showed a lot of resolve for the third match in a row at home and just managed to close the game down in the end.
“I’m very relieved, it was good for the lads who came on in the end and I thought our scrum was good, with Dylan (Hartley) and Paul Hill.
“We got some crucial penalties at the set piece and I’m very relieved to close the game down.”
And he added: “It was nervy, sevens like at times, but at least we got the win.
“We’ve got a couple of weeks away from the Premiership now because we go into the Anglo-Welsh so we’re looking forward to that.”