Djibril Cissé scored a penalty at the death as battling Russian side Kuban Krasnodar held Swansea to a 1-1 draw in Europa League Group A at the Liberty Stadium.
Cissé converted a penalty two minutes into injury time after Ibrahima Balde was taken out of the game late by Gerhard Tremmel.
Michu had given Michael Laudrup's side the lead on 68 minutes after he darted onto a pass over the top from Alvaro Vasquez to bravely nudge the ball under the Kuban goalkeeper Aleksandr Belenov.
It was his sixth goal of the season, and his fourth goal of this European campaign.
Swansea are top of Group A with seven points from three games. Valencia are second with six points from their three fixtures after they trounced St Gallen 5-1.
Kuban remain bottom of the section despite holding Swansea to a draw, but they were well worth the point after playing some good football in the second half.
Laudrup's side felt that the visitors were worth the point, but Jonjo Shelvey will regret losing possession in the fateful few seconds before Kuban unearthed their equaliser.
Valencia's romp to a comprehensive victory over St Gallen in tonight's other group fixture moves the Spanish team onto six points, and Swansea have plenty of work to do to reach the last 32.
There had been few bright points during a tepid first half, but the hosts would have led had Shelvey kept his composure.
Michu's first-time pass found the midfielder in acres of space, but his rushed shot was nowhere near finding the target.
Wilfried Bony volleyed over and Shelvey prodded wide from rare examples of incisive Swansea play, while at the other end Tremmel shovelled Maksim Zhavnerchik's drive wide and Dwight Tiendalli was fortunate to escape a red card after hauling down Lorenzo Melgarejo.
The hosts finally found some control after the break, with Michu making another telling intervention by racing onto a smart Alejandro Pozuelo pass to beat Belenov as he raced from his goal.
But they were pegged back in injury time after Tremmel brought down Balde having delaying his decision to come out to meet the striker, and Cissé made no mistake.