Complications are welcome for Celtic.

Nobody at the club will protest too vehemently that traditional routines have been disrupted by the Champions League schedule. A period of readjustment began last season, when groups of players were granted staggered breaks before preparations for the William Hill Scottish Cup final.

The hope is to implement similar initiatives during this campaign, even if the short nature of the summer holiday is still unnerving. "It feels as if we haven't been away really," said Neil Lennon. "The cup final feels as if it was the weekend past."

The Celtic manager spent one week away with his family, but it is the challenges that lie ahead which will refresh him. Before the league title defence begins in earnest, he needs to guide his team through three qualifying rounds if they are to reach the Champions League group stages.

There are upheavals to manage, too. The signings of the striker Amido Balde and the centre-back Virgil van Dijk will add brawn and presence to the team, while the futures of Victor Wanyama and Gary Hooper remain uncertain.

Lennon has to prioritise, with the first leg of the second-round qualifying tie against Cliftonville taking place in Belfast in just under three weeks. New players will be integrated, but other individuals can also be counted on afresh. There have been times when Lennon has seemed wary of relying on Anthony Stokes, but he has never been inclined to dismiss the merits of the forward. He describes him as a "rascal", and the manager might never demand saintliness among his players, but Stokes has regularly undermined his worth to the team with indiscretions.

Lennon valued him enough to be tolerant, even if he had to act like an authoritarian at times. He considered the patience worthwhile after Stokes recalled the best of his all-round game in the 3-0 victory over Hibernian at Hampden to win the Scottish Cup. Now the player is likely to sign a contract extension, and the manager is prepared to invest more faith in him.

Stokes' value to the squad is in the range of his abilities, since he combines goalscoring prowess with a creative edge. "I never doubted his commitment, I just doubted his discipline problems," Lennon said.

"You don't want to take the devil out of him but it was affecting his performances on the field as well. Then it becomes 'right, you're out of the team, and the team flourishes [while] you're sitting there looking in. It's nobody's fault but your own.'

"You've got to learn from those mishaps, but we've all crossed the line in terms of discipline so I'm quite comfortable with it. He's a great lad – he just lets himself down. He has that self-destruct button at times but he's tending to shy away from that now."

Stokes can be headstrong, and a trip to Dublin last year to attend a memorial for Alan Ryan, a commander of the Real IRA, led to him being disciplined by Celtic. An ankle injury curtailed his appearances last season, but Lennon also previously left him out of high-profile games. That was a result of the manager's doubts about his application, but that is no longer an issue. The spell on the sidelines, and the consequences of his lapses of judgment, caused Stokes to reconsider his behaviour, at least as far as Lennon observed.

There were headlines recently about a confrontation with an Elvis impersonator at a nightclub, but Lennon is prepared to dismiss them as trivial accusations. Having sought Stokes' explanation of the incident, the Celtic manager believes that it was "blown out of proportion", not least because the club has yet to be contacted by the police.

When he talks about responsibility, it is only about the player's ability to play up front on his own, but Lennon is intent on considering Stokes a reformed maverick rather than anything more troublesome.

"I saw a difference in him last year," the manager said. "He's still only 24, he's not fully matured yet, but he's intelligent enough to know. He has retracted some of the stuff from last year, he knows he let himself and the club down. The injury, and sitting-out of the Champions League games, sparked something in him. He showed what a very good player he can be when he puts his mind to it. The penny should drop with him. He has been inconsistent. If he can be consistent over a concerted period of time, we'll have another good player on our hands."

The Champions League remains a defining tournament for Celtic, since failing to reach the group stages will leave supporters feeling somewhat bereft.

The domestic campaign would feel mundane, too, even if Lennon's side do comfortably retain the title. Competing in the group stages raises profile as much as revenue, and Celtic were enhanced by their participation last season. Fans pine for trophies, and the absence of Rangers from the top flight makes the treble seem more attainable, but Lennon sets his ambitions by different criteria.

"It would be a great achievement if we could make the group stages. Honestly, I'm not saying that lightly, with the shorter break and the extra tie as well," Lennon said. "Does it put less emphasis on the domestic football at times? It probably does because the Champions League brings so much to the pot and the fact that we are getting £12 million bids for players is probably due to the performances they put in in Europe. Our priority is the Champions League and the league. It only takes one off-day and bang goes the treble. Is it a yardstick for me? No."