O'Neill desperate to follow the Leeds lead and bounce back

Martin O'Neill could have been in charge of Leeds United had it not been for heavy legal pressure. On Tuesday night, he will settle for a carbon copy instead. Had Leicester City not threatened to sue their then manager three seasons ago when Leeds came calling, then he, and not David O'Leary, would now be at Elland Road.

Celtic proved heaven-sent compensation but O'Neill remains intrigued by Leeds. The shattering defeat by Porto last week has dented ambitions of reaching the next phase of the Champions' League, yet the Parkhead manager hopes his team follows the lead of O'Leary's side.

Just over a year ago, Barcelona humbled Leeds in the Nou Camp. Leeds picked themselves up off the floor, learned from the 4-0 thrashing and went on to reach the semi-finals. Celtic must recover their poise from the pounding they took in Portugal and negotiate their way past Rosenborg in the Lerkendal Stadium to keep alive their hopes of qualifying from Group E.

"All good sides suffer a heavy defeat at some stage," reflected O'Neill on Friday, having had time to watch the video tape of the lesson handed out by Porto, who struck three – though it could easily have been six – against a defence upon which the Northern Irishman prides himself. "I don't want to make comparisons with Leeds, who are an excellent side, but they took a beating along the way last year and they learned and we have to do the same."

O'Neill also conceded that O'Leary was able to go out and spend £18m on Rio Ferdinand to strengthen the FA Premiership side for the second phase of Europe's most demanding competition. The Celtic manager, in contrast, will have to transform the same men who let him – and 8,000 followers in the Das Antas Stadium – down so badly. Rosenborg may be out of the equation now in Group E, but few teams have won in chilly Trondheim during the Norwegian club's seven successive years among the elite.

Celtic have to succeed on Tuesday where such sides as Real Madrid and Bayern Munich have failed if they want to take the issue into the last match, when they face Juventus at Parkhead on 31 October.

"We want to be going into the Juventus game with that one meaning something, but we have to learn from the Porto match. They were excellent but we allowed them to play.

"Our own performance was really disappointing but we have to recover. There is no easy way for us now, but I am not giving up the ghost. If we have to go to Rosenborg and win, then we will have to do that."

O'Neill has been forced to revise his own calculations, which predicted qualification if 10 points were in the bag. It is now likely to be 12: two wins are paramount to hoist Celtic up to that summit. He must look wistfully at other groups where teams could qualify with fewer points, notably Arsenal. One of the reasons has been Rosenborg's failure to match the results of previous seasons.

Yet, that is not taken as a sign of weakness, according to Johan Mjallby. The Swedish defender refers to Rosenborg as Scandinavia's footballing flag-bearers. "It is a pity that they cannot go through now because they are a good side," said Mjallby. "They have excellent players, but they have been unlucky in every game. They were well organised against us in Glasgow but they also had some good individuals, who would not look out of place at Europe's top clubs."

Mjallby was part of the Celtic defence whose reputation was shredded in Porto, yet there were few fiercer critics than the rugged Swede himself. "It was a dreadful night," he reflected. "We were taught a lesson in European football and it was not nice. I cannot remember us winning a single challenge and that's unacceptable.

"We missed important headers, our distribution was bad – it was schoolboy stuff. Normally we defend as a team but this time we were all over the place."

The man who is a double for the screen tough-guy Dolph Lundgren growled: "We have to beat Rosenborg and Juventus to go through now." O'Neill is hoping that this time the script goes to plan.