Steve Wigley made a losing start to his new career as head coach at troubled Southampton as Bolton held out under late pressure to smash their second win of the Premiership season.
Bolton scored twice in the first 26 minutes and then sat back to soak up Southampton's increasing pressure, although Saints created few genuine chances.
Trotters manager Sam Allardyce demanded a better performance after the poor display in the defeat at Fulham and he got it from his players who had the greater discipline and flair in a one-sided first half.
The visitors were ahead after seven minutes when Henrik Pedersen was one of two Bolton players left clear by a pass from Nicky Hunt.
As Southampton appealed in vain for offside, Pedersen strode on to beat the unprotected Antti Niemi.
Gary Speed almost added another after 14 minutes with a shot from 20 yards and Jay-Jay Okocha blasted an effort narrowly wide from an even greater distance.
Bolton went further ahead in the 26th minute when Stelios Giannakopoulos was brought down by the lunging Danny Higginbotham for an obvious penalty and from the spot-kick Okocha sent Niemi the wrong way.
Southampton chairman Rupert Lowe, who sacked Paul Sturrock on Monday after only 13 matches in charge, came in for some heavy criticism from chanting fans.
Rattled Saints had Rory Delap booked for a foul and it was not until the 31st minute that they had their first chance, a long-range effort from Fabrice Fernandes being pushed around the post by the Bolton goalkeeper.
At least the home side were better in the second half with Bolton content to sit on their lead, but the Trotters defence was not often breached.
Ivan Campo was booked for a foul on Kevin Phillips and at the other end, in a rare Bolton second half raid, Radhi Jaidi headed narrowly over the bar from a Stelios corner.
Southampton improved when the gangling Peter Crouch replaced Delap in the 68th minute and a seconds later James Beattie headed narrowly over the bar from a centre by the dangerous Fernandes.
With six minutes remaining, a cross from the right by Paul Telfer was mishandled by Jussi Jaaskelainen and Crouch bundled the ball over the line.
There was still time for Southampton to mount a series of desperate attacks in search of an equaliser and deep into injury time Claus Lundekvam headed narrowly wide with the goalkeeper beaten, as a centre from Fernandes found its way through to him in a packed penalty area.
Anxious Allardyce sent on Fernando Hierro in place of Pedersen and Les Ferdinand came on for Kevin Davies as the Saints threw everything at the Bolton goal.
But new boss Wigley had nothing to celebrate when referee Steve Dunn blew for full time.
When he did so, another hail of abuse was hurled by Southampton fans at their chairman, whose appointment of Wigley was his seventh in six years.
Bolton were celebrating an important victory, looking more like the side which humbled Charlton on the opening day of the season, but they almost paid the penalty for committing themselves to deep defence for the entire second period.