Rubin Kazan vs. Chelsea (1-3 aggregate)
Rubin's gameplan in Europe usually relies on keeping things tight, but they were outclassed in suffering a 3-1 defeat at Stamford Bridge. A 2-0 victory is not beyond the SIberians, but they'll have to bring their A-game and come out and play if they want to progress. Chelsea have been inconsistent and are suffering from an exhausting fixture-list, so there may be some hope for the hosts.
FC Basel vs. Tottenham Hotspur (2-2 aggregate)
Basel put themselves in a decent position with a 2-2 draw at White Hart Lane, so Tottenham will need to come out and attack in Switzerland in order to progress. The two away goals will be a nice cushion for the hosts, and with Gareth Bale and Aaron Lennon missing from Tottenham's ranks, they may struggle to find the result they need. A big potential for an upset.
Lazio vs Fenerbahce (0-2 aggregate)
Fenerbahce made the most of their home form to give themselves an excellent 2-0 lead, so Lazio have it all to do at the Olimpico. An away goal for the Turks could bury the tie once and for all, so this game will be balanced on a knife edge. Lazio certainly have what it takes to progress, but the visitors are clear favourites as it stands.
Newcastle vs. Benfica (1-3 aggregate)
Newcastle took the lead in Portugal but were soon on the end of an onslaught from Benfica which condemned them to defeat, although a precious away goal could still mean a lot. Their victory at the weekend over Fulham leaves them relatively safe in the Premier League, so this could be their main focus. It'll need a heroic performance, but at St. James' Park, they have more than a chance.