With the batsman already under serious scrutiny after a woeful performance in Brisbane, the tourists were all out for a paltry 172 on day three in response to Australia's 570 for nine declared.
Mitchell Johnson once again ripped through England's line-up, taking seven for 40, while the only England batsmen to emerge with any credit were Michael Carberry and Bell, who both contributed half-centuries.
Bell looked in splendid touch in his 72 not out, but despite his best efforts, England will have to dig deep to avoid falling 2-0 down in the five-match series, with the hosts extending their lead to 530 after closing on 132 for three in their second innings.
"It was thoroughly disappointing," Bell told Sky Sports 2 "A very good wicket here and we haven't given our bowlers any opportunity to get back in the game.
"It's disappointing, the guys are hurting but I can reassure you they are training and doing everything they possibly can to put this right in the second innings."
England's fighting spirit has been questioned in some quarters after their third collapse of the series.
However, Bell said: "As a group over a number of years, we've shown the amount of fight we have in that dressing room.
"We haven't put it quite right so far on this trip but there's a lot of guys in there with a lot of cricket still to go in this series that will show people that we have got the fight.
"It starts tomorrow and the last day so we certainly have to fight hard.
"As an England team, we haven't done anything close to what we're capable of doing and what we should do for everyone else watching."
Bell's ability to handle Australia's bowlers, and Johnson in particular, has led to renewed calls for the Warwickshire man to move up the order to number three.
Joe Root was given the nod after Jonathan Trott returned home, and although the 22-year-old appeared comfortable in the role, he was one of seven batsmen guilty of giving their wicket away on Saturday when he swept the first ball he faced from off-spinner Nathan Lyon to deep square-leg.
Bell added: "We'll see, it's not my decision really.
"I've just got to go and do what I can for the team. I'm happy to bat anywhere for the team but I thought Rooty played very, very well until that dismissal.
"I thought he shaped up brilliantly against the new ball."