Poland international Saganowski bagged the only goal after just 54 seconds as Southampton bounced back from Tuesday's 2-1 reverse at Coventry City.
The on-loan Troyes striker picked out the bottom right-hand corner with a wonderful glancing header to convert teen sensation Gareth Bale's free-kick after Djamel Belmadi had been bundled over.
The Saints were watched by their second biggest crowd of the season of 27,974 but the masses witnessed a dire match.
In a game of few clear-cut opportunities, Trinidadian striker Kenwyne Jones was guilty of some woeful finishing.
The in-form Jones should have doubled the home side's lead in the 26th minute after the impressive Andrew Surman had carved open Ipswich's defence.
Surman picked out Jones with a threaded throughball but the striker's tame shot was easily gathered by Ipswich goalkeeper Lewis Price.
Algeria international Belmadi had also wasted a good opening less than a minute earlier.
Surman was again heavily involved, playing a one-two with Belmadi before the midfielder volleyed straight into the arms of a grateful Price from 12 yards.
Jones summed up a frustrating opening half when he shot straight at Price from the edge of the penalty area five minutes before the interval.
Ipswich's best chance of the half fell to midfielder George O'Callaghan in the 39th minute. Owen Garvan and Alan Lee combined to set up O'Callaghan for a shooting chance only for the former Portman Road goalkeeper Kelvin Davis to spread himself and beat the ball away.
Winger Gary Roberts had earlier fired over after Lee and Garvan had again linked up on the left-hand edge of the box.
Belmadi picked up the only booking of the game a minute into the second half after catching full-back Dan Harding with a late challenge.
Jones was presented with another glorious chance to add to his recent goal tally of five in his last six games ten minutes later.
Man-of-the-match John Viafara shrugged off two Ipswich defenders before picking out Jones 10 yards out but the misfiring forward rattled the inside of Price's right-hand post.
Jones fired into the stands seven minutes later after Colombia international Viafara had again cut the Ipswich defence to ribbons.
Davis was on hand to deny his former pals for a second time in the 72nd minute with another wonder-save.
Left-back Harding came marauding down the wing before whipping in a teasing cross which substitute Jon Walters met with a bullet close-range header but Davis somehow stuck out his right arm to turn the ball behind for a corner.
Viafara came close to being rewarded for a fine midfield display with a rare goal 11 minutes from time when he broke free down the right before shooting over from the edge of the area.