Dundalk almost escaped from Belarus with a positive result.
The League of Ireland Premier Division champions withstood the onslaught from BATE Borisov for 70 minutes, before being undone by a defensive slip, a clever finish from Mikhail Gordejchuk, and a telling pass from a former Arsenal and Barcelona winger.
Alexander Hleb, a second-half substitute in the Champions League third-round qualifier first-leg, intercepted a pass from Sean Gannon and played in his teammate, who finished beyond Gary Rogers.
Dundalk must overcome the 1-0 deficit next week at Tallaght Stadium to progress to the final qualifying round of Europe’s top club competition.