Benfica are many people's favourites to win the UEFA Europa League, so it goes without saying that the Eagles have quality in their ranks.
Here, we detail five players the Portuguese side boast that Chelsea simply can't ignore, and for those of you who are watching as neutrals, be sure to pay attention to these talents.
Who joins Ezequiel Garay in our list?
Former Chelsea player Nemanja Matic is arguably Benfica's best player, and the the Blues' hierarchy will be hoping that sanctioning his sale isn't a major regret on Thursday morning.
The Serbian moved to the Eagles as part of the David Luiz deal and has blossomed into one of the finest holding midfielders in world football. Impressed with Morgan Schneiderlin? Matic is better.
He's a fantastic reader of the game, passes neatly and spots interceptions early; Jorge Jesus' side have a good chance of cancelling out Chelsea's No. 10 with him in place.
Oscar Cardozo was the main man at the Estadio da Luz for a long while, but Lima is now rising to the fore.
Lima joined Benfica on the final day of the 2012 summer transfer window, displacing the former incumbent immediately by scoring in consecutive starts.
He's netted a total of 27 goals this season and shown versatility by playing in midfield.
There are question marks over Jorge Jesus' starting XI, but Ola John's fine form in the UEFA Europa League so far could see him take his place.
Operating from the left, there are few more skillful—John jinks his way through defences with ease and has the quality to deliver superb balls into the box.
He'll definitely feature opposite Eduardo Salvio if Jesus opts for a 4-2-3-1 formation.
Benfica have two fine central defenders, but Ezequiel Garay is the one to watch if you're a Chelsea official or an English Premier League fan.
He's quick, comfortable on the ball and lethal in the box, and Chelsea will be hoping David Luiz can offer some inside information on how to limit his influence.
Nicolas Gaitan is maddeningly inconsistent, but when he's on form, he's a real jaw-dropper of a midfielder.
Playing out on the right or through the middle he can cause Chelsea problems, and once he gets going, he's really tough to stop.
If Jorge Jesus opts for the 4-2-3-1 formation, the Argentine will play as a No. 10 and go head-to-head with the Blues' defensive midfielders.