Glenavon produced a superb performance despite a 2-1 defeat against KR Reykjavík in Iceland on Thursday night.
Manager Gary Hamilton planned to keep the tie alive for the second leg at Mourneview Park and that is certainly the case with a vital away goal.
That goal came from Simon Kelly as he gave the visitors the lead on 14 minutes. Andy Hall curled over a corner and the big Dublin man found the net to make it 1-0.
KR fought back but the Glenavon defence work hard to protect the lead. It was not all one way traffic with Glenavon breaking quickly and Mark Sykes having an effort saved by the home keeper.
Just when it seemed the Lurgan Blues would go into the break ahead, the home side plundered an equaliser on 40 minutes.
The home side forced the pace after the restart but still Glenavon looked comfortable, defending well and dealing with anything KR could throw at them.
However, on 78 minutes substitute Andrew Doyle was adjudged to have committed a foul in the box and the referee pointed to the spot. Holmbert scored from the spot kick to put the home side ahead.
It was in the latter stages of their last Europa League tie in Iceland that Glenavon faded with tired legs and conceded late goals that proved their downfall, but not on this occasion. Indeed, they were unlucky not to salvage a draw with a late effort from Eoin Bradley just inches over the bar.