Our team of reporters have the answers as you look to tinker with your Fantasy squad ahead of the second legs.
Article top media content
The 16 sides left in the competition have contrasting missions in the second legs: some, such as Barcelona and Arsenal, have big deficits to try to recover, while the likes of Benfica and Sevilla face tough away games defending narrow leads.
So where do our team of reporters think the best Fantasy picks can be found?
Arsenal (Andy Brassell, @UEFAcomAndyB)
Alexis Sánchez (FW, €9.6m) is Arsenal's key player – and fresh, having surprisingly been used as a substitute for Saturday's loss at Liverpool, in which he made a goal after coming on. Danny Welbeck (FW, €6.5m) was the Gunner on target at Anfield, underlining how dangerous and unpredictable he can be.
Atlético Madrid (Joe Walker, @UEFAcomJoeW)
With five goals, including one in the first leg, and two assists in his last six outings, Atlético talisman Antoine Griezmann (FW, €10.3m) is a must-have, especially given his side's likely counterattacking ploy. Jan Oblak (GK, €6.1m) missed the first leg through injury, yet remains the Rojiblancos' leading points scorer this season. He has conceded just two goals in six competition games.
Barcelona (Graham Hunter, @BumperGraham)
The obvious one though Lionel Messi (FW, €12.5m) was nullified in the first leg. Only twice in Messi's career has he scored more UEFA Champions League goals in a season than he has managed already this term – ten – and he's netted 38 times in all competitions. He's also contributed 13 assists across the entire campaign and hit the woodwork nine times. If Barcelona have any chance, it's on this genius.
Bayern München (Jordan Maciel, @UEFAcomJordanM)
Bayern have rediscovered their free-scoring form since the 5-1 first leg win in Munich and Robert Lewandowski (FW, €11.1m) has contributed six goals in four matches. Arsenal know they will need to go for it if they want any possibility of pulling off the unthinkable, which should create space for the Bavarian team to attack.
Benfica (Paul Bryan, @UEFAcomPaulB)
"A Greek God" is how one Portuguese paper recently described Kostas Mitroglou (FW, €6.1m) and with his side likely to counterattack against Dortmund, the in-form striker (15 goals in his last 13 in all competitions, including the first-leg winner) could be worth a punt. Benfica may well come under pressure in Germany, so Luisão (DF, 4.5m) will be required to keep the visitors focused – as well as offering set-piece prowess at the other end.
Borussia Dortmund (Steffen Potter, @UEFAcomSteffenP)
Picking Pierre-Emerick Aubameyang (FW, €10.0m) is a no-brainer. BVB need goals and the Gabon forward is their go-to guy. Plus he will want to make up for that disastrous first leg, where he squandered a penalty and wasted a couple of great opportunities.
Juventus (Paolo Menicucci, @UEFAcomPaoloM)
I wouldn't be surprised to see Juventus keep a clean sheet at home to Porto and left-back Alex Sandro (DF, €5.4m) is also a good asset in attack as the assist for Dani Alves in the first leg showed. Miralem Pjanić (MF, €7.5m), in peak form and always a major threat from set pieces, could also be a good option and so could Paulo Dybala (FW, €8.2m) who is returning to his best.
Leicester City (Simon Hart, @UEFAcomSimonH)
A late Jamie Vardy (FW, €7.3m) strike in the first leg gave Leicester a lifeline, his first goal of 2017; he has since looked reinvigorated with two goals and an assist in the Foxes' two subsequent Premier League outings. The quick passes upfield of Danny Drinkwater (MF, €5.9m) could be crucial too while Kasper Schmeichel (GK, €5.7m) – brilliant in Seville – will have to be his usual reliable self.
Bayer Leverkusen (Matthew Howarth, @UEFAcomMattH)
If Leverkusen stand any hope of overturning their 4-2 first-leg deficit at Atlético, two players will have a big role to play. Javier Hernández (FW, €7.8m), who last scored in the competition in September, must rediscover his shooting boots, while Kevin Kampl (MF, €6.5m) will have to display the bravery and battling spirit he showed in orchestrating the defeat of Tottenham at Wembley in November.
Manchester City (Simon Hart, @UEFAcomSimonH)
The evidence of the thrilling first leg in Manchester is that goals will be on the menu at the Stade Louis II and the timely reminder of the scoring prowess of Sergio Agüero (FW, €10.1m) in recent weeks indicates he could have a key part to play once again. City's in-form wide men, Raheem Sterling (MF, €7.5m) and Leroy Sané (MF, €6.8m), may also be worth considering for goals and assists.
Monaco (David Crossan, @UEFAcomDavidC)
Kylian Mbappé (MF, €4.6m) is a must-buy. The 18-year-old frightened City with his pace and skill in the first leg and took his goal magnificently. Monaco are capable of scoring "a thousand million goals" as Josep Guardiola quotably said, and that means you have to find room for Radamel Falcao (FW, €7.9m), though the Colombian did miss the weekend game v Nantes with a muscular problem.
Napoli (Paolo Menicucci, @UEFAcomPaoloM)
While I would avoid Napoli's defenders, because the Partenopei have to take risks against forwards with great pace in their attempt to recover 3-1 arrears, Napoli could score at home. The creative Lorenzo Insigne (FW, €6.7m), the cheapest among their attackers, found the net in Madrid for his fourth goal in his last ten games on all fronts, yet also had an assist in each of Napoli's last two matches against Juventus and Roma.
Paris Saint-Germain (Chris Burke, @UEFAcomChrisB)
Paris's defenders can expect a busy night in Barcelona, but Unai Emery's men are sure to get openings on the break – and Julian Draxler (MF, €8.5m) boasts the dynamism, pace and eye for goal to be a potent menace at Camp Nou. On target in the first leg, the Germany winger will once more relish the chance to run riot down Barcelona's weaker right flank.
Porto (Paul Bryan, @UEFAcomPaulB)
Porto need goals and their January signing from Vitória Guimarães, Francisco Soares (FW, €6.4m), has been supplying them lately. His strong physical presence could unsettle Juventus, the forward playing just ahead of André Silva (MF, €7.1m), who has four assists and 15 Liga goals this term. Having been substituted early in the first leg after Alex Telles's first-half dismissal, he'll be especially keen to show his worth in Turin.
Real Madrid (Joe Walker, @UEFAcomJoeW)
Karim Benzema (FW, €10.7m) notched twice and got an assist against Eibar at the weekend and is the Merengues' top scorer in the competition this season with five in seven. Toni Kroos (MF €7.2m) is the Spanish Liga's joint-top assist provider with nine and a fundamental part of this Madrid outfit. He doesn't just make them tick in midfield and ghost into goalscoring positions from deep, he also takes corners and wide free-kicks.
Sevilla (Graham Hunter, @BumperGraham)
Sevilla's outstanding player all term, Steven N'Zonzi (MF, €6.0m) comes not only at a cheap price but with three wins in four career meetings with Leicester. UEFA.com's key player three times for the Rojiblancos in this tournament, including the first leg, the organising central midfielder helps to explain Sevilla's record of not having conceded once away from home.