Ipswich missed out on automatic Premiership promotion after drawing with Brighton, which was enough to keep the Seagulls in the Championship.
Joe Royle's side had the perfect start when Shefki Kuqi put them ahead after just four minutes.
But their lead was quickly erased when Adam Virgo's turning volley brought Brighton back into the game.
Ipswich had a later penalty appeal turned down but it made no difference in the wake of Wigan's win.
Both Wigan and Ipswich had gone into the final game of the Championship level on points but Wigan's victory over Reading moved Ipswich into the play-offs.
Ipswich took the lead when Kuqi found the target for the 19th time this season.
Some dire defending by Virgo let the Finnish striker run clear on Bent's pass and he fired the ball past the diving Alan Blayney.
But Virgo made amends within five minutes with a superbly-taken left-footed volley as he turned his man.
Gary Hart rose superbly to head Richard Carpenter's curling free-kick goalbound, but Kelvin Davis pulled off an excellent reflex save only to see Virgo find the target with the rebound.
Both sides had chances in the remainder of a niggly first half, which saw a trio of innocuous yellow cards dished out.
Ipswich could consider themselves unlucky, however, after appeals for a penalty were turned down when Bent was brought down in the area by Charlie Oatway on the half-hour mark.
They came out for the second half determined to grab the win, with manager Joe Royle playing four strikers for the final 15 minutes.
Brighton keeper Blayney halted two relatively straightforward chances in the opening 15 minutes of the half.
First he held onto a weak Jim Magilton free-kick and then covered a Bent strike after the front man had been put clear by Kuqi.
Brighton's best chance of the half came with 20 minutes left when the terrier-like Leon Knight whipped the ball across the face of the goal, but Dean Hammond hoofed it into the ground.
That combination also came close in the final five minutes but Hammond under-hit his pass to Knight.
The home side's fans had to endure a nervous final 20 minutes as Ipswich's strikers harangued them.
Defeat would have dropped them a division but they did just enough to hold on.
Brighton: Blayney, El-Abd, Butters, Reid, Harding, Hart (McPhee 82), Oatway, Carpenter, Knight (Robinson 88), Hammond, Virgo.
Subs Not Used: Mayo, Nicolas, Shaaban.
Goals: Virgo 10.
Ipswich: Davis, Wilnis (Diallo 40), De Vos, Naylor, Unsworth, Magilton, Miller, Westlake, Currie (Counago 64), Bent, Kuqi, Diallo (Scowcroft 75). Subs Not Used: Horlock, Price.
Booked: Kuqi, Magilton.
Goals: Kuqi 4.
Ref: M Jones (Cheshire).