Tension hangs over Borussia Dortmund's training headquarters in the northern suburb of Brackel.

Ahead of Wednesday's UEFA Champions League playoff second leg against Sporting, an uneasy atmosphere surrounds last season's Champions League finalist.

As Dortmund's struggles in the Bundesliga continue to worsen, the team has shown two vastly different faces in domestic and European competition.

Gerrit Holtmann (R) of VfL Bochum vies with Julien Duranville of Borussia Dortmund during the German first division Bundesliga football match between VfL Bochum and Borussia Dortmund in Bochum, Germany, Feb. 15, 2025. (Photo by Joachim Bywaletz/Xinhua)

A 2-0 defeat to underdog Bochum followed a dominant 3-0 first-leg victory in Lisbon, highlighting the club's ongoing inconsistency. Despite a strong Champions League campaign, turmoil persists.

Guinean international Serhou Guirassy exemplifies the team's dual nature. After scoring 28 league goals for Stuttgart in the 2023-24 season, the 28-year-old has managed just nine in 19 Bundesliga appearances since joining Dortmund last summer. Yet in the Champions League, he has thrived.

Leading the tournament's scoring chart ahead of stars like Robert Lewandowski and Erling Haaland, Guirassy has tallied 10 goals and five assists. He has been directly involved in all of Dortmund's goals in the competition, making him their most vital offensive asset this season.

The forward has played a crucial role in Dortmund's six wins across their last nine Champions League matches.

Club officials and captain Emre Can have praised Guirassy as "an inspiring link between midfield and the front line, combining efficiency with deep runs."

Despite their European success, Dortmund's Bundesliga struggles continue to weigh heavily on the club.

Newly appointed coach Niko Kovac is working to ease tensions, but Austria national team coach Ralf Rangnick has criticized Dortmund for lacking a clear tactical identity since Jurgen Klopp's departure in 2015.

With 10 managerial changes in less than a decade, the club's struggles reflect an ongoing identity crisis. The issue, Rangnick suggested, is not the players but Dortmund's failure to establish a consistent playing philosophy.

Since replacing Nuri Sahin, Kovac has lost his first two league matches, and his rescue mission is already facing challenges.

Trailing by eight points in the Bundesliga's Champions League qualification race, Dortmund must not only advance past Sporting but also secure victories against Union Berlin and St. Pauli to avoid further unrest.

Kovac's challenge is to restore stability while the club appears headed for major structural changes after the season.

For now, Dortmund's Champions League hopes rest largely on Guirassy.

With his 13th assist in a Borussia Dortmund shirt this season, he has set a new club record for a player in a Champions League campaign, surpassing former Dortmund stars Lewandowski and Haaland (10 and 12, respectively).