Neil Lennon described reaching another Champions League group stage as his greatest achievement in football last night but then claimed his job sometimes felt "impossible" because of intense criticism and negativity.

Celtic beat Shakhter Karagandy 3-0 to reach the group stage for the second consecutive season, which will bring at least £16m and the likes of Bayern Munich, Barcelona, Real Madrid, Mancheser United or Chelsea to Parkhead over the coming 3½ months.

The draw for the group stage begins at 4.45pm tonight in Monaco. Celtic will be fourth seeds but the benefits of qualifying again were immediate last night as they agreed a fee of around £3m with Schalke for Teemu Pukki. They will now attempt to negotiate acceptable personal terms with the 23-year-old Finnish striker. The Israeli midfielder Nir Biton, 21, arrived in Glasgow yesterday to complete a £700,000 move from FC Ashdod.

"I think the carrot of the Cham­pions League might be a big draw for a lot of players," said Lennon. "It puts us in an excellent position. Biton will sign, work permit permitting, but they are going to have to play well to get into that team. I'm not joking." When asked if others were close to coming Lennon said "you are asking the wrong man".

He went on: "There is a great sense of pride in what we have achieved tonight, considering we lost Gary Hooper, Victor Wanyama and Kelvin Wilson, who have been the spine of the team for the last year and a half. I'm angry as well, angry at the reaction towards the team after the first leg. The environment here is all wrong, there's far too much negativity. These players have given everything for the club and they put Scottish football in a really good light last year.

"I wouldn't even say they had a bad night last week, they just didn't take their chances having created plenty. Yet the hysteria afterwards was disgusting. It may have come from some quarters of the media, it may even have come from some quarters of our own support, but the knee-jerk reaction to one average performance is baffling to me. It just makes the job impossible at times.

"Managers nowadays, there's no respect for the position. They are analysed and scrutinised in everything they say. There are times when I call the game as I see it in the cold light of day and still get slaughtered for it or people try to humiliate you. I think that's totally wrong and it doesn't do the prestige of the job justice. We live in an age of phone-ins, an age of internet pseudo-intellectuals and an age of millions of pundits with an opinion.

"When I got back [from Kazakhstan] last week, I watched the game back on ITV4 and I was taken aback by the commentary. It was so anti us, it was unbelievable really. That's the second time ITV have been really disrespectful to our club. Last year, when the group stage draw was made, someone in their company tweeted 'bye, bye Celtic'. This club is not a laughing stock. It has a great history and I have some great, talented young players here who performed heroic­ally tonight. They will all get pats on the back tonight but it's all super­ficial in my eyes. We don't have a divine right to be in the Champions League.

"That's five qualifiers we have played in the last two seasons and they are so difficult to overcome. I don't think people appreciate that and certainly the reaction for the last seven or eight days really turned me. While I am very proud I don't really get that huge sense of enjoyment out of it.

"It's the greatest thing I've ever done in football. The last three months have all been about preparation for this. We lost three very important players and it's been very difficult to replace them. Coming from a two-goal deficit tonight just makes the players' performance and efforts even more remarkable. I cannot speak highly enough about the players in that dressing room tonight. They were just wonderful."