The January transfer window could prove pivotal for Bundesliga basement boys Mainz, with a lack of signings potentially leading to relegation. Here are three signings they could make in the winter window.
Mainz’s main transfer targets
Silas
The wing wizard from the Democratic Republic of the Congo is on Mainz’s radar. A proposed move in January wouldn’t be that geographically challenging for Silas, with his current employers, fellow Bundesliga outfit Stuttgart.
Attractively versatile, with the ability, not only in his natural position, but also as a right-sided midfielder or solo striker.
However, what makes a potential switch debatable is that Silas hasn’t actually played a minute of football across the 2025/26 campaign. His last appearance came on loan while playing for Red Star Belgrade against Vojvodina at the end of March.
While that might thwart a move from happening, an ongoing ankle injury that has restricted Silas to the treatment room ever since might completely rule out negotiations from taking place.
That could potentially be why Stuttgart are yet to offer him a contract extension, with his current deal due to expire this summer. Die Roten’s reluctance to secure an updated signature on the dotted line could be Mainz manager Urs Fischer’s gain.
It could appear that Mainz are leading the queue for a striker who was playing Champions League football last season and was also a Serbian SuperLiga winner.
In December, Mainz came agonisingly close to upstaging Harry Kane and Bayern Munich, who finished top of the Bundesliga calendar year table by a huge margin, so if Fischer and Co want to be playing Bundesliga football next season, they need to outmatch every other side in January.
Borna Sosa
It appears recently-appointed manager Fischer is looking to strengthen at both ends of the pitch throughout a potentially all-important January transfer window.
With Mainz rooted to the foot of the Bundesliga table after winning only one of their 15 matches, last season’s sixth-placed finish now appears a distant memory.
If Die Nullfünfer need to reinforce their squad depth up top, they certainly need to firm up their defence as well, considering their current league position.
Already familiar with the Bundesliga after over a century of appearances for Stuttgart between 2018 and 2023, the current Crystal Palace attack-minded left-back could be heading back to the top-flight of German football.
Sosa has played in just three Premier League appearances across 2025/26 from 20 possible opportunities, with a loan move reported as the best solution for all parties involved. With Sosa joining from Ajax in August last year, a permanent move doesn’t seem to be on the cards at the moment.
Hampus Skoglund
To conclude, the latest rumours surrounding Mainz’s potential signings this month is Hammarby’s 21–year-old Swedish right-back Skoglund.
With Die Nullfünfer already linked with Sosa, it could be a completely new look full-back partnership come the end of the January transfer window.
However, Mainz’s upper hierarchy will have to be quick, with Wrexham also being linked with Skoglund’s potential signature.
The sought-after defender helped Hammarby finish in second position in the Allsvenskan last season behind eventual champions Malmö, ultimately confirming the club’s qualification for the Conference League.
Skoglund played in all four of his current side’s matches in this season’s competition, but was left disappointed after they were knocked out by fellow Scandinavian side Rosenborg in the third round of qualifying. With some European experience under his belt, it looks like Mainz are ready to open up the cheque book to secure his long-term signature.
