GROUP A
Group A is the only mini-league which contains four champions - leaving Manchester United to revisit old territory against Bayern Munich.
BAYERN MUNICH
The holders emerged unbeaten with four wins from the first group stage.
Ottmar Hitzfeld's side look in no mood to surrender their crown after scoring 14 goals in their six matches.
Bayern are a team packed with experience and quality under their masterly coach, and present a real threat.
NANTES
Nantes may be regarded as one of Europe's lesser lights, and are currently bottom of the French league.
But the French game is rich in talent and no-one should take them for granted following two wins over Lazio in the first group stage.
MANCHESTER UNITED
Sir Alex Ferguson's 1999 Champions League winners are striving to repeat their success, but will need to improve on patchy first phase form.
United, however, may flourish in the later stages as their world class summer signings Juan Sebastian Veron and Ruud van Nistelrooy come into their own.
United's players are also desperate to give their retiring manager the perfect send-off in his homeland at Hampden Park in May.
And despite scratchy form, no-one would back against them with confidence.
BOAVISTA
Boavista were the surprise side in Liverpool's group in the opening games, performing impressively and with steel as well as silk.
The Portuguese champions will be confident after their confidence-boosting displays and must not be taken lightly.
GROUP B
The group of re-matches, with Liverpool renewing acquaintance with Barcelona and AS Roma after defeating them on the way to winning last season's Uefa Cup.
BARCELONA
Barcelona have been in magnificent form in Europe, winning five games out of six.
They are also in great form in La Liga, and men like Rivaldo and Patrick Kluivert will be thirsting for revenge after their Uefa Cup semi-final defeat against Liverpool.
Barcelona only qualified for the Champions League in injury time on the last day of the Spanish season, thanks to an incredible Rivaldo strike, and the Catalans have a massive incentive to overshadow Real Madrid to establish supremacy in Spain.
LIVERPOOL
Liverpool have restored their European reputation with a magnificent run of form in Europe.
Their confidence will be boosted by victories over group opponents AS Roma and Barcelona last season.
England pair Michael Owen and Steven Gerrard will be vital to the cause.
GALATASARAY
Galatasaray will present formidable opponents for any side in their hostile home environment of Istanbul, but are arguably the weakest team in the group.
AS ROMA
The Italian champions, under the shrewd guidance of Fabio Capello, will be another world-class side on a revenge mission against Liverpool.
Gerard Houllier's men knocked them out of the Uefa Cup last season, and of course beat them on their own turf in the 1984 European Cup Final.
Roma still possess great quality in Gabriel Batistuta, Brazilian defender Cafu and Francesco Totti.
GROUP C
Real Madrid look odds on to qualify, but stand by for a dogfight between the remaining three teams.
REAL MADRID
Real are 3-1 tournament favourites, even though they are under-performing badly in their domestic league.
They have added Zinedine Zidane to Luis Figo in their glorious array of talent and want another symbolic Champions League win to celebrate their centenary.
Steve McManaman continues to flourish in Spain despite his struggles on the international stage with England, and he will be hoping to add another Champions League winners' medal to the one he picked up in 2000.
PANATHINAIKOS
The Greeks will also be backed by a fanatical home crowd, and proved their quality by beating Arsenal in Athens and finishing ahead of them in the first group stage.
Their temperament can be their inspiration and their downfall - must not be ignored.
PORTO
Porto have strengthened and developed since they were comfortably beaten by Liverpool in last season's Uefa Cup.
They outclassed Celtic and will fancy their chances of moving through the group with Real Madrid.
SPARTA PRAGUE
Outsiders but highly dangerous. Sparta showed their mettle by earning a draw against Bayern Munich in Germany and have improved since losing to Arsenal at Highbury last season.
GROUP D
This is a high-quality group which finds Arsenal faced with a tough task to realise their ambition of fulfilling their potential in the Champions League.
JUVENTUS
"The Old Lady" of Italian football is attempting to revive her former glories under returning coach Marcello Lippi.
Juventus fielded an under-strength squad when they lost to Celtic at Parkhead, but still had stars like Del Piero and Trezeguet on target.
DEPORTIVO LA CORUNA
Brilliant Spanish side tipped by many to win the trophy, especially after completing a double over Manchester United with a stunning and thoroughly deserved win at Old Trafford.
Striker Diego Tristan sunk United and is rated at £30m - a future world star.
ARSENAL
Arsenal must improve dismal away form to have any chance of making progress.
They will also be handicapped by Dennis Bergkamp's fear of flying and the lack of a cutting edge - but still have the quality in their squad to beat anyone.
Patrick Vieira and Thierry Henry will both want to build on their successes in France 98 and Euro 2000 by adding success in the Champions League to their portfolio, but Arsenal have a brittle nature away from Highbury which threatens their ambitions.
BAYER LEVERKUSEN
Workmanlike German side who will ignore their status as rank outsiders to bank on solidity and reliability as their tools to lever a path into the next stage.