Are Mainz in trouble this season?

In their eighth successive Bundesliga season, Mainz are right to feel part of the furniture. But after the sale of their most outstanding player and a so-so first half of the season, are the Carnival Club in relegation trouble?

Even when Mainz were competing in the UEFA Europa League, Christian Heidel's ambitions were completely modest. "We want to finish, at least, 15th, we'll see after that…" Heidel, the former sporting director who served for more than two decades, once said.

Heidel's successor Rouven Schröder, a sharp, intelligent operator with a background in technical scouting, is under the spotlight in his first year in charge. While head coach Martin Schmidt has the task of leading his side to points each week, the future of the club lies in the hands of Schröder. This month, the club was rocked by the sale of Yunus Malli, the team's key player, to Wolfsburg for 12 million euros. Such was the abruptness of the 24-year-old's departure that most of his teammates were told by SMS.

To say that Malli, previously a target for Dortmund and Leverkusen, carried Mainz over the last 18 months would perhaps be a little extreme. But the German-Turk's clean finishing, nimbleness and effective decision-making has given Mainz the additional quality required to push into the top-half of the table. He is one of the most incisive attacking-midfielders in the division with six goals and six assists for the Carnival Club.

The impact of his loss long-term – and without a proven replacement – is unclear, but a 0-0 draw at home to Cologne illustrated why he would be such a loss. Mainz managed to create just a handful of good opportunities, though generally struggled to penetrate the compact defensive lines of one of the league's best teams at the back.

Without Malli, Mainz are probably facing their toughest season since the most-recent return to the Bundesliga in 2008. Schröder has already had to deal with losing the spine of his team before this season. Loris Karius, the imposing number one keeper, joined Liverpool, while Julian Baumgartlinger signed for Bayer Leverkusen after five seasons as a mainstay in Mainz's midfield. As expected, it has taken time for Mainz's core players to adjust to the Bundesliga.

Therefore, it's little surprise that Mainz's defensive structure was so weak this season. Replacement keeper Jonas Lossl hasn't quite brought the same commanding presence between the sticks. Communication with his centre backs has also been a problem – but largely because the regular pair of Niko Bungert and Stefan Bell have rarely featured in the Bundesliga.

With 30 goals conceded, Mainz are bottom-three defensively, although, Gleave points out that in terms of major chances conceded to the opposition this season "Mainz's defence is 13th best in the league." It remains to be seen how Mainz's defensive performances will play out across the next four months.

Eleventh in the table, talk of relegation trouble sounds puzzling. But it's this refined collective structure, which was so pivotal under Schmidt last season and his predecessor Thomas Tuchel. Without that, and their best attacking player, it's hard to see how Mainz can match their 20-point haul from the first half of the campaign – two more than last term.

"It wouldn't surprise me at all if they had a better second half of the season and finished higher than now,” concludes Simon Gleave, Head of Analysis at Gracenote. 

"A repeat of sixth place probably won't happen but a place in the top half (which they are only 2 points off now) doesn't seem out of the question."

The effects of European football on the first half of the season certainly cannot be overlooked. Mainz qualified for the UEFA Europa League group phase for the first time in its history this season. It added an extra six games to the schedule, and while Mainz appeared to be comfortable handling the demands early on, Schmidt's side couldn't recover from heavy defeats in Europe ahead of Bundesliga weekends.

Given Mainz's simple resources, the inability to manage a Europa League-Bundesliga schedule is no surprise; even clubs in stronger economic conditions have found this pattern hard to master. So many changes from game-to-game and in particular rotation in central defence has caused instability in Mainz's defence.

On Sunday, Borussia Dortmund are the visitors to Mainz for their first home game of 2017, the Ruhrpott side boosted by the return of top scorer Pierre-Emerick Aubameyang following his short stint at the Africa Cup of Nations. 

"Dortmund have more quality in every area compared to Cologne, so our approach will have to be different," said Schmidt.

At the numerical halfway point of the Bundesliga, Mainz can be delighted with their position in the league. Schröder has asked for the players to hit 40 points, which would be enough to stay clear of Hamburg, Mönchengladbach and the likes.

Though relegation wouldn't be a disaster for Mainz given the excellent foundations in place, there's no chance the Carnival Club will be giving up without a fight.