Celtic 1-1 Boavista
Celtic's bid to reach their first European final for 33 years hangs in the balance after they were held at home to Boavista in the Uefa Cup semi final first leg.
Henrik Larsson was the saint and sinner for Celtic at Parkhead - scoring the equalising goal but missing a penalty kick.
The Portuguese side provided muscular, well-organised opposition and were given a gift of a goal when Celtic defender Joos Valgaeren put the ball into his own net.
Celtic had the lion's share of possession but lacked the midfield invention to break down Boavista and squandered the second half chances that came their way.
Celtic started at a whirlwind pace and had the Portuguese side pinned back for long spells without creating any clear goal-scoring chances.
The best early opportunity fell to Larsson in the seventh minute but he was stretching to meet John Hartson's neat pass and could only poke the ball wide from 10 yards.
Belgian referee Frank De Bleeckere did nothing to endear himself to the 60,000 crowd by failing to punish Boavista for three handball incidents in the first 12 minutes, two inside the visitors' penalty box.
Celtic were given a fright in the 18th minute when Pedrosa broke and crossed to Luiz Claudio, who directed the ball back into the path of Duda, but the striker's shot deflected off Bobo Balde and spun wide.
With Boavista defending deep and in numbers there was precious little space for Larsson to exploit and, with goalkeeper Ricardo commanding his area, crosses to Hartson were also proving fruitless.
The second half was just three minutes old when the noisy crowd were stunned by Valgaeren's own goal.
The Belgian defender slid across his goalkeeper Rab Douglas in a bid to block a low cross from Martelinho, but only succeeded in diverting the ball into the net with his studs.
Celtic's reply was immediate and parity was established within a minute when Larsson stroked home his 26th European goal.
Larsson saw his penalty kick saved by Ricardo
A cross from Neil Lennon was delightfully cushioned into Larsson's path by Stilian Petrov and the Swede drilled home from eight yards.
Douglas made a good save from a Pedrosa free kick in the 58th minute and four minutes later Ricardo had to deal with a raking set-piece effort from Larsson.
Hartson was given a glimpse of goal in the Boavista penalty box but could not connect with his shot properly and the ball looped harmlessly into the arms of Ricardo.
The Welshman had a better chance when the ball landed at his feet just a few yards out in the 72nd minute, but he could only stab it straight at Ricardo.
Celtic were handed a fabulous opportunity to go in front 15 minutes from time when they were awarded a penalty for yet another hand ball.
However, a flying save from Ricardo denied Larsson from the spot.
Ricardo almost handed Celtic a late winner when he fumbled a cross into the path of Hartson, but Turra was on hand to clear the striker's goal-bound shot.
In injury time Hartson saw a header flash inches wide of the target.
Celtic: Douglas, Mjallby, Balde, Valgaeren, Agathe, Lambert,
Lennon, Petrov, Thompson, Larsson, Hartson. Subs: Marshall,
Sylla, McNamara, Fernandez, Maloney, Smith, Crainey.
Boavista: Ricardo, Mario Loja, Paulo Turra, Avalos, Erivan,
Eder, Anunciacao, Martelinho, Pedrosa, Duda, Luiz Claudio. Subs:
William, Rui Oscar, Jorge Couto, Bosingwa, Jocivalter, Cafu,
Referee: F De Bleeckere (Belgium)