Helmes apologies for penalty misses
Helmes said he had never previously missed a spot-kick but watched in horror yesterday as his was the only strike saved by the hosts' goalkeeper Christofer Heimeroth during the extra-time penalty shoot-out.
Helmes had earlier fired wide when he was fouled in the penalty area on 63 minutes which would have put his side 1-0 up in normal time.
But after the match finished 1-1 in regulation time his second miss proved costly, sealing 'Gladbach's 5-4 win and the hosts' place in the third round.
"I'm sorry for the guys," said Helmes. "This is not a pleasant situation for me, but I have been through things like this before and I managed to put them behind me.
"I will also get out of this situation again. Perhaps Arturo (Vidal) should have taken the first penalty, but I have never missed one."