Two unbeaten sides in all competitions this season – Sporting Lisbon and Chelsea – meet at the Estadio Jose Alvalade in Lisbon in Day 2 UEFA Champions League (UCL) matches.

Jose Mourinho’s side have been in good form in the premier league, but they stuttered to a 1-1 draw against Schalke in their Group G opener. That puts more pressure on them to win in Lisbon, where the Blues will be hoping to call upon top scorer Diego Costa, who has a nagging hamstring problem.

The heavyweight clash of the day is at Parc des Princes where French champions, Paris Saint-Germain lock horns with Barcelona.

The clubs clashed in the quarter-finals 18 months ago, when PSG held their more illustrious opponents in both legs but lost on away goals. They will be desperate to win this one after drawing four of their last five matches of the season.

Bayern Munich beat CSKA home and away in the group stage of last season’s UCL and the Russian champions’ hopes of getting a result this time will not be helped by the fact the match will be played behind closed doors at the Arena Khimki.

CSKA are being punished by UEFA for the bad behaviour of their fans during a group-stage match last season.

After conceding late to go down 1-0 to Bayern in their group opener, the visit of Roma is already a must-win game for Manchester City.

City have scored 11 goals in winning their last two matches, but a game against a Roma side who have won all five Serie A games so far and thrashed CSKA Moscow 5-1 two weeks ago promises to be a stiff test for the English champions.

Below are the match backgrounds to Tuesday’s key games.

SPORTING VS CHELSEA

• Sporting have won their last three home games against English visitors without conceding a goal. The only defeat in nine such contests (W7 D1) was Manchester United’s 1-0 victory in the 2007/08 group stage, Sporting’s only previous UEFA Champions League encounter with a Premier League club.

• Their 19 previous games against English sides have ended W9 D3 L7.

• This is their sixth group-stage campaign and the first since 2008/09, when they reached the last 16 for the first time.

• The 2013/14 Portuguese Liga runners-up are unbeaten in 16 European home games − 13 wins, three draws − since a 2-0 loss to Brondby in the 2010/11 UEFA Europa League play-offs.

• Chelsea’s record in nine games against Portuguese clubs – three against Benfica, six versus FC Porto – in European competition is W7 D1 L1. Their last six wins against Liga sides were by single-goal margins.

• Their last victory came against Benfica in the 2013 UEFA Europa League final when Branislav Ivanovic’s header in the last minute of added time earned a 2-1 win at the Amsterdam Arena.

• The 2012 UEFA Champions League winners made it to last season’s semi-finals, where they were beaten by Club Atletico Madrid 3-1 at home after a 0-0 draw away.

• This is their 13th group stage campaign and 12th in a row.

PSG VS BARCELONA

• The French champions are looking for their first Group F victory after an opening draw at AFC Ajax (1-1).

• They are unbeaten in 29 European home games (19 wins, 10 draws) dating back to a 4-2 loss to Hapoel Tel-Aviv FC in the UEFA Cup group stage in November 2006.

• Laurent Blanc’s men won four of their five home games in the 2013/14 competition, beating Benfica (3-0), Olympiacos FC (2-1), Bayer Leverkusen (2-1) and Chelsea (3-1).

• Their home record against Spanish visitors is W5 D4 L1. That solitary loss was a 3-1 defeat by Deportivo La Coruna in the 2000/01 UEFA Champions League second group stage.

• Barcelona had an opening home victory over APOEL FC (1-0) but they have lost four and won just two of their last eight UEFA Champions League away games – at Celtic (1-0) on match day two last season and Manchester City (2-0) in the round-of-16.

• Barcelona’s record away to French sides is W3 D3 L2.

• They last won on French soil at Olympique Lyonnais in the 2001/02 first group stage, Xavi Hernandez appearing in a 3-2 victory.

CSKA VS BAYERN

• CSKA’s only home victory in the 2013/14 UEFA champions league came in St Petersburg, where they had to play FC Viktoria Plzen due to the condition of their Moscow pitch – and won 3-2.

• They have won just one – and lost five – of their last seven UEFA competition home games in Moscow.

• CSKA won their two previous home meetings with German opposition, both in the UEFA champions league, 1-0 v Hamburger SV (2006/07), 2-1 v Wolfsburg (2009/10).

• Match-day-one winners against Manchester City (1-0), Bayern were undefeated in 10 UEFA champions league away games prior to their 2013/14 semi-final loss at Real Madrid (0-1).

• The Bavarians’ overall away record in last season’s competition was W4 D1 L1.

• Their away record against Russian sides is W4 D3 L1. Their only defeat was at FC Zenit (0-4) in the 2007/08 UEFA Cup semi-finals.

CITY VS ROMA

• At home in last season’s competition, the English champions posted two wins (5-2 v CSKA Moscow, 4-2 v FC Viktoria Plzen) but also two defeats (1-3 v Bayern, 0-2 v Barcelona).

• Aleksandar Kolarov’s equaliser in the 1-1 draw with Napoli in the 2011/12 group stage maintained City’s unbeaten record at home to Serie A sides (W2, D2, L0).

• City’s most recent victory, home or away, against an Italian team was the 3-0 triumph against AC Milan in the 1978/79 UEFA Cup third round, which secured a 5-2 aggregate success. Brian Kidd, now assistant manager, scored in both legs.

• Roma opened their Group E campaign with a 5-1 home win against CSKA.

• They have won only once in 14 previous visits to England: 1-0 at Liverpool FC in the 2000/01 UEFA Cup fourth round. Even then, they lost the tie 2-1 on aggregate.

• They have lost on all three previous visits to Manchester, too – all at Old Trafford where Daniele De Rossi (who scored) and Francesco Totti played in the 7-1 UEFA Champions League quarter-final defeat by Manchester United in 2006/07.

• Their most recent visit to England brought a 1-1 draw at Fulham in the 2009/10 UEFA Europa League group stage.

THE FIXTURES

Group E

CSKA MOSCOW V BAYERN MUNICH

MANCHESTER CITY V ROMA

Group F

APOEL V AJAX

PARIS SAINT-GERMAIN V BARCELONA

Group G

SCHALKE 04 V MARIBOR

SPORTING V CHELSEA

Group H

BATE BORISOV V ATHLETIC BILBAO

SHAKHTAR DONETSK V FC PORTO