Jim Mallinder backed referee Wayne Barnes’ decision to dismiss Worcester captain Jonathan Thomas in Saints’ 30-14 win at Franklin’s Gardens on Saturday.
Thomas saw red in the 52nd minute for punching Northampton No.8 Sam Dickinson, who was shown a yellow for pulling back lock James Percival in the build-up to the incident.
Barnes, refereeing a Saints game for the first time since sending off Dylan Hartley in the Premiership final last May, carded a total of four players, with Warriors flankers Leonardo Senatore and Sam Betty also binned.
But Saints boss Mallinder was in agreement with the official’s decisions.
“You can’t go punching to the head, can you?,” he said of the Thomas sending off. “It’s something you can’t do.
“He’s a good referee is Wayne Barnes. He’s one of the best we’ve got.”
Winless Worcester had threatened to spring a big surprise as they headed in at half-time just three points down.
But Saints scored three times in the second half - a penalty try and two GJ van Velze efforts - to secure their ninth successive Premiership win and 10th in a row in all competitions.
And despite the fact they failed to claim the bonus point, Mallinder said: “We’re top of the league, which is a pretty good place to be to be honest.
“It’s in international weeks when we’ve got a number of our best players missing and a number of them still injured as well.
“It’s slightly frustrating that we couldn’t get the bonus point in the last few minutes, but very pleasing we’re still in winning ways.”
“There’s always little bits you can work on and we knew Worcester were coming here buoyed by last week’s performance and that they’d be competitive.
“They picked a big, heavy pack and stopped us mauling, legally or not, but they stopped us.
“We knew that like when we went down to Worcester earlier this season, that if we kept moving the ball and kept playing decent rugby the gaps would appear, and so it proved.”