Chris Boyd was left to reflect on a 'painful' defeat for Saints as Leicester Tigers secured a 23-15 success on derby day at Twickenham.
Tries from Jamie Gibson, David Ribbans and Mike Haywood were not enough for the black, green and gold as they failed to make their territorial dominance count.
Tigers took their chances on the counter-attack and fly-half George Ford was able to land two conversions and three penalties, while his counterpart, Dan Biggar, missed all of his kicks at goal.
Saints were hoping to earn the victory to send Rob Horne home happy, but the Australian, who was forced to retire after suffering full paralysis of his right arm in a game at Leicester last season, was not able to see his former side win.
And boss Boyd said: "At the end of the day, we didn't control the middle third of the field.
"We made too many errors across the board and it would be grossly unfair to single out one person on that.
"We need to be tighter on playing the type of game we're trying to play.
"Every game we've played we've expected to play well enough to win and the loss is painful, the fact it's a local derby is painful and the fact we want to respect Rob Horne, who is very well regarded in the club, is very painful.
"It's not a very happy changing room, but life goes on."
Leicester were forced to defend for long periods of the game.
But in the end, their clinical first-half performance proved good enough.
"We probably tried to play too much," Boyd said.
"We had 60 or 65 per cent possession in the middle third of the paddock against Bath and just let them in with a couple of key errors as well so the intention was to play a bit more territory this time.
"I thought we kicked well but we didn't chase particularly well and the outcome on the back of that wasn't terribly profitable for us.
"We made a couple of errors and they got a couple of softish tries before half-time.
"We were never able to peg it back."