Here's a look ahead to Wednesday's Champions League action as Atletico Madrid meet Bayern Munich in a rematch of last season's semi-final and Manchester City look to maintain their perfect start to the campaign at Celtic (all kick-offs 1845 GMT):
Ludogrets Razgrad (BUL) v Paris Saint-Germain (FRA)
It is all even in Group A with PSG squandering a host of chances before having to settle for a 1-1 draw at home to Arsenal in their opener while Ludogorets claimed a 1-1 draw away at Basel. PSG are under pressure to get a result after a patchy start to the season including a 2-0 defeat at Toulouse on Friday that left them fourth in Ligue 1. Serge Aurier, who was sent off in that game, is available for selection despite being handed a two-month prison sentence on Monday for assaulting a police officer. Marco Verratti is available after his red card against Arsenal was overturned. The Bulgarian champions have six Brazilians in their squad but two of them, full-backs Vitinha and Cicinho, are injured. The match will be played at the national stadium in Sofia, nearly 350 kilometres away from Razgrad, where Ludogorets' own ground is not considered up to scratch for major European games.
Arsenal (ENG) v Basel (SUI)
Things are looking up for Arsenal after they came from behind to hold PSG in their opener, seemingly putting them in control of the group. The Gunners marked Arsene Wenger's 20th anniversary as manager by beating Chelsea 3-0 on Saturday, leaving them third in the Premier League and unbeaten in seven games in all competitions. Alexis Sanchez scored his fifth of the season in that game having also netted in Paris. However Arsenal, who lost to Olympiakos in their opening home group game last season, should be wary of Basel. Swiss champions in each of the last seven seasons, they needed a Renato Steffen equaliser to draw with Ludogorets but have a 100 percent domestic record. Ivory Coast international Seydou Doumbia is their leading scorer.
At Istanbul, Turkey
Besiktas (TUR) v Dynamo Kiev (UKR)
After on-loan Talisca's last-gasp equaliser secured a 1-1 draw against his parent club Benfica last time out, Turkish champions Besiktas entertain Dynamo Kiev at their impressive Vodafone Arena in Istanbul. Senol Gunes' side are unbeaten this season and warmed up for the game by coming from two goals down to draw 2-2 at home to Galatasaray. In what could be a wide-open group, Ukrainian champions Dynamo were beaten at home by Napoli in their opener and had Serhiy Sydorchuk sent off, meaning the midfielder will be suspended for this game. Serhiy Rebrov's side had suffered three defeats in four outings all told before bouncing back to beat Olimpik Donetsk 4-0 at the weekend despite leaving several regulars on the bench.
At Naples, Italy
Napoli (ITA) v Benfica (POR)
Last season's Serie A runners-up Napoli underlined their credentials in the group by winning 2-1 in Kiev in their opener thanks to a brace from Polish striker Arkadiusz Milik, who has settled well since signing from Ajax to help replace Gonzalo Higuain. Maurizio Sarri's side are still unbeaten this season but so are Benfica, who top the Portuguese league after a 2-0 win at Chaves on Saturday. Indeed, the two-time former European Cup winners are unbeaten in 17 games overall since losing to Bayern Munich in the first leg of last season's quarter-finals. Greek midfielder Andreas Samaris misses the trip due to injury.
At Moenchengladbach, Germany
Borussia Moenchengladbach (GER) v Barcelona (ESP)
Barcelona's trip to Germany to take on Gladbach will see goalkeeper Marc-Andre ter Stegen come up against his hometown team, whom he left in 2014 to move to Spain. The Catalans are without the injured Lionel Messi and Gladbach will hope to take advantage of that to keep alive their hopes in the group after going down 4-0 at Manchester City last time out. Barcelona, in contrast, trounced Celtic 7-0 at the Camp Nou with Messi netting a hat-trick. In addition to the Argentine, Samuel Umtiti is sidelined for Barca, who were 5-0 winners at Sporting Gijon at the weekend. The Borussia-Park is not an easy place to go -- Andre Schubert's side have won their last 11 games in front of their own fans after a 2-0 victory against Ingolstadt in the Bundesliga on Saturday.
At Glasgow, Scotland
Celtic (SCO) v Manchester City (ENG)
Celtic Park is the venue for the latest Scotland v England showdown. The Hoops last beat Premier League opposition a decade ago when Shunsuke Nakamura's superb free-kick saw off Manchester United, but the financial chasm between Scottish football and the Premier League has only widened since then. It is now extremely difficult for Celtic to compete with Europe's giants, as exemplified by their 7-0 loss in Barcelona last time out, their record European defeat. Celtic may have beaten Kilmarnock 6-1 at the weekend to consolidate their place atop the Scottish Premiership, but City are a daunting prospect. Pep Guardiola's Premier League leaders have won all 10 games they have played this season although Kevin De Bruyne has joined Vincent Kompany on the sidelines.
Atletico Madrid (ESP) v Bayern Munich (GER)
It is a repeat of last season's semi-final at the Vicente Calderon as Bayern visit Atletico looking for revenge for their defeat in that tie. The Bavarians now have Carlo Ancelotti at the helm, the Italian who coached Real Madrid to their dramatic Champions League final win over Atletico in Lisbon in 2014. The clubs also met in the 1974 final with Bayern prevailing in a replay, but Diego Simeone's Atletico are formidable in front of their own fans and unbeaten this season so will be hopeful of ending Bayern's perfect record so far in this campaign. Bayern, who won 1-0 at Hamburg at the weekend, are without Brazilian winger Douglas Costa while Atletico are missing Augusto Fernandez. The midfielder suffered an anterior cruciate ligament injury in Sunday's 1-0 win over Deportivo that will keep him out for much of the remainder of the season.
At Rostov-on-Don, Russia
Rostov (RUS) v PSV Eindhoven (NED)
These two sides both lost on matchday one, with Rostov being thumped 5-0 at Bayern while PSV lost 1-0 at home to Atletico. This will be Rostov's first ever home game in the group stage and they will be hoping to repeat their 4-1 win against PSV's Dutch foes Ajax in the play-offs that took them through 5-2 on aggregate. PSV, the 1988 European Cup winners, have not won on their travels in the Champions League proper since defeating CSKA Moscow in Russia in 2007/08. PSV, who are without Jurgen Locadia, won 3-1 at Excelsior at the weekend while Rostov warmed up for this game with a 1-0 victory at home to Lokomotiv Moscow.