Jared Borgetti snatched an injury-time winner for Bolton to give them victory over Lokomotiv Plovdiv in their Uefa Cup first round, first leg tie.
Plovdiv took the lead against the run of play when Vladimir Ivanov advanced down the right and crossed for Boban Jancevski to sweep the ball home.
Wanderers levelled when El-Hadji Diouf headed home Nicky Hunt's cross.
And Borgetti made sure Bolton's first European game ended in triumph when he netted from a tight angle.
Wanderers had made four changes from their goalless draw with Blackburn at the weekend.
Hidetoshi Nakata made his first start for the club, with Hunt, Radhi Jaidi and Ricardo Gardner also coming into the side.
But manager Sam Allardyce did not alter the direct approach he utilises in the Premiership and his side's strategy of launching balls into the visitors' penalty area was effective early on.
They were winning everything in the air and Bruno N'Gotty went close to opening the scoring when he beat Plovdiv keeper Stoyan Kolev to Nakata's cross in the fourth minute but saw his header bounce wide of the goal.
Another N'Gotty header was cleared off the line soon afterwards, this time from a whipped Stelios Giannakopoulos delivery.
Plovdiv were on the back foot but the first clear-cut chance of the game still went their way, when Jussi Jaaskelainen spilled a routine through-ball and had to react quickly to deny Jancevski.
The Bulgarians began to threaten more themselves, particularly when they swiftly turned defence into attack.
Several times Bolton were out-numbered on the break and that approach saw Plovdiv take a shock lead on 28 minutes.
Ivanov collected the ball and played a neat one-two with Ilami Halimi before racing down the right flank and crossing for Jancevski to power the ball home.
The goal sent the tiny contingent of Plovidiv fans wild and Allardyce's side initially struggled to find anything to silent them.
Gardener and Giannakopoulos were seeing plenty of the ball on either flank but the quality of their delivery into the area was sadly lacking.
That pattern continued into the second half, with Bolton enjoying the lion's share of possession but struggling to open up the visitors.
It was only when Allardyce brought on Borgetti midway through the second-half - as support for Diouf up front - that their fortunes began to change.
And the equaliser that the home fans craved came on 72 minutes when Hunt sent a searching ball into the cross and Diouf dived full length to nod it into the bottom corner.
That should have been the platform for an onslaught from the home side in the last quarter of the game - but it never materialised.
Substitute Fabrice Fernandes brought a fine save out of Kolev with two minutes left but Plovdiv looked comfortable as the game moved into injury time.
However, with seconds left Nakata flicked on a Fernandes cross towards Borgetti on the right-hand side of the area and he composed himself before drilling the ball into the far corner of the net.
The Plovdiv players felt play should have been stopped as Jancevski needed treatment - and also felt Borgetti was offside.
But the goal stood and it means Bolton have a slight, but important, advantage for the second leg in a fortnight's time.
Bolton: Jaaskelainen, Hunt, N'Gotty, Jaidi, Gardner, Campo, Giannakopoulos (Fernandes 67), Okocha (Nolan 67), Nakata, Pedersen (Borgetti 57), Diouf.
Subs Not Used: Walker, Davies, O'Brien, Faye.
Booked: Nakata, Gardner.
Goals: Diouf 72, Borgetti 90.
Lokomotiv Plovdiv: Stoyan Kolev, Ivanov, Georgi Iliev (Vandev 81), Halimi (Georiev 45), Tunchev, Kotev, Krasimir Dimitrov, Krizmanic, Robert Petrov, Djordani, Jancevski (Stoinev 90).
Subs Not Used: Vasil Kamburov, Zalatinski, Mihaylov, Hristev.
Booked: Jancevski, Georgi Iliev, Djordani.
Goals: Jancevski 28.
Ref: Darko Ceferin (Slovenia).