West Ham's great start to the season has seen summer signings such as Aaron Cresswell, Alex Song, Diafra Sakho and Enner Valencia all playing starring roles.
Yet with Winston Reid's contract situation threatening to become a distraction, manager Sam Allardyce may need to delve into the transfer market again in January.
New Zealand international Reid, 26, is out of contract next summer, and with the likes of Arsenal, Liverpool and Manchester United believed to be interested, West Ham need to make contingency plans for his possible departure.
With that in mind, reports over the weekend suggested that the Hammers were scouting Austrian centre back pairing Aleksandar Dragovic and Martin Hinteregger.
Dragovic, 23, and Hinteregger, 22, have both been linked with big moves to the likes of Arsenal and Liverpool in the last 12 months, but currently ply their trades with Dynamo Kiev and Red Bull Salzburg respectively.
However, if Reid goes then West Ham would surely on be able to bring in one of the centre backs, so which one should they prioritise?
Dragovic has long been touted for stardom since impressing with Basel, and has all the attributes to replace Reid - he's quick, strong, calm in possession and good in the air. He's a year older than Hinteregger, and it shows - there are fewer errors and fewer kinks to iron out for a potential buyer.
Yet being further along in his development can also be a problem - Spartak Moscow opened the bidding for Dragovic at £12m earlier this week, and West Ham will need to match or even better that to land him.
Meanwhile, Hinteregger is promising but slightly less polished right now. He hit the headlines with this stunning goal, but the lead up to the strike shows what he can do. He's slightly shorter than Dragovic, but quicker across the ground, and his swift turn to escape defenders shows his development as a ball playing defender.
However, Hinteregger commits the occasional error, largely down to lapses in concentration - demonstrating that there is still work to do with the young defender. He should be cheaper than Dragovic at this stage in his career, but gives Allardyce something to mould if they do pursue a deal.
For an instant challenge for European football, Dragovic offers a great transition and arguable upgrade on Reid, whilst if planning more the future, Hinteregger could be the better option - it simply depends what Allardyce wants.