Die Borussen were defeated by a solitary Vicente Iborra goal in the 70th minute, spoiling an otherwise solid, if unspectacular, display from the Germans in Spain.
The first half instantly indicated just how little is to choose between the current Europa League Champions Sevilla and Bundesliga high-flyers Mönchengladbach.
With little in the way of clear cut chances in the early stages, birthday-boy Kramer had a real chance in the 20th minute when he fired a low drive on goal following good work from Wendt. Rico in the Sevilla goal got down well to save, however.
The hosts had a half-chance just three minutes later, when a cross from Vitolo sailed past everyone and narrowly went wide.
Rico was called to make another stop in the 33rd minute as Raffael found Fabian Johnson at close range, but his effort was well stopped to maintain parity.
The sides went in deadlocked at 0-0 in the first half, but fans of Borussia will no doubt have been encouraged and impressed with the way the side played without fear against the holders in the first 45.
The Fohlenelf continued this positivity in the early stages of the second period, with Oscar Wendt coming close in the 50th minute, dragging his shot wide right from the left edge of the box following a lay-off from Thorgan Hazard.
Yann Sommer had his first real save to make in the 57th minute as Carlos Bacca rose to nod goalwards, but it was a comfortable save, which emphasised just how solid the defensive effort of Mönchengladbach had been to this point.
As is the case with most visiting teams in the first leg, the main objective is always to get an away goal. There was a sense of ‘Gladbach forcing the issue slightly, and they were caught when Sevilla opened the deadlock in the 70th minute.
Victor Iborra stole in at the near post from Figueiras’ pull-back on the right byline, deflecting the ball goal-bound and sending it past a despairing Sommer in the Borussia goal. It was an important goal for Sevilla, who had limited chances through the whole game, but they took the one that mattered and it was evident just how crucial the goal was.
The remaining 20 minutes passed disappointingly without much incident, and Sevilla help on for an unconvincing but professional 1-0 victory. Lucien Favre and his side will be disappointed not to have grabbed an away goal given the way they controlled the game in stages, but rest assured the Borussia-Park will be rocking for the second leg and backing the turnaround.