Argentine Ezequiel Garay and Yannick Djalo both remain absent due to injury, while Pablo Aimar returns after missing Benfica's last Champions League game due to suspension.
Aimar came off the bench in the goalless draw with Olhanense at the weekend, but was only on the pitch for 17 minutes, as he received a red card. It will be interesting to see whether Jorge Jesus decides to stick with Aimar on the bench or reinstate him, particularly with him now facing a domestic suspension.
Artur is Benfica's only fit player who is one yellow card away from a suspension.
Chelsea have Raul Meireles back from suspension, though he may not be picked anyway, with all of Roberto Di Matteo's midfielders fit and available.
Branislav Ivanovic is a major doubt after missing the draw with Spurs at the weekend, so Jose Bosingwa is on standby to deputise once again.
Cole and Luiz are both one yellow card away from a European suspension.
There is the usual competition up front, with Drogba and Torres both vying for the lone striker spot.
Benfica welcome English opposition to the Estadio da Luz for the second time this season, having already assisted in knocking Manchester United out of the Champions League in the group stage. The Portuguese side held United to a draw both home and away and proved more than a match for them.
Chelsea meanwhile, will have been boosted massively by their dramatic extra-time win over Napoli in the last round, though domestic results since then have not been overly impressive. A resounding win over second-tier Leicester was followed up by a loss at Man City and a dull 0-0 draw with Tottenham - a game that they came extremely close to losing.
Benfica have lost only once and drawn twice at home this season, despite having played 17 games on their own turf, including being unbeaten at home in European competition this season. Chelsea have lost 4 of their last 5 on the road, and the only one of those that they did not lose was away at Birmingham. Benfica will be underestimated by many, but they have made it to the quarter finals of the Champions League on merit. They will give Chelsea a tough time on home soil and will be hopeful of taking a lead into the second leg, albeit a slender one.
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