As Celtic prepare for the home return match which should see them progress to the next round, they most absorb the bad news that they will be without John Hartson for the rest of the season
The Scottish league leaders said on their official website that scans carried out on Monday had revealed "a deterioration in one of the Welshman's disks, the one above that which required surgery last season".
The 28-year-old is expected to have the operation this week and will be out for four months.
Meanwhile, his strike partner Henrik Larsson must shrug off thoughts of an international recall from Sweden to help propel the Hoops on another UEFA Cup run.
The 32-year-old is the subject of a campaign led by UEFA president Lennart Johansson and the Swedish government to return him to the international fold for Euro 2004.
However, for now the former Feyenoord man is concentrating on defending Celtic's lead in the third round, second leg rather than getting carried away by thoughts of repeating of last season's thrilling run to the final.
Larsson said: "We haven't been thinking about another UEFA Cup run because it's too far away and we have to treat this game against Teplice with the utmost respect.
"We still haven't done anything yet this season. We have a head-start in the league and we are 3-0 up from the home tie, but there is still a lot of football to be played. There are no guarantees."
Midfielder Stephen Pearson is relishing his first taste of competitive football on foreign soil. The Scotland international has managed to hold down a regular first-team place among the big names at Parkhead since his £350,000 move from Motherwell in January.
Pearson said: "It's been like a dream for me. I never thought I would be in this situation and I'm making the most of it."
Celtic will be without half a dozen players tonight. Defender Ulrik Laursen has dislocated a shoulder. Striker Shaun Maloney also faces months on the sidelines after a serious knee injury.
Neil Lennon is suspended while Johan Mjallby (knee) and Liam Miller (groin) are not yet fit.