The Champions League returns this week for the second round of fixtures in the new-look competition.

Here, the PA news agency looks at the key talking points with five British sides in action.

Arsenal seeking first win as PSG visit

After a disappointing goalless draw away to Atalanta in their Champions League opener – in which David Raya made a fine save to keep out Mateo Retegui’s penalty – Mikel Arteta’s side face another big challenge with the ambitious Paris St Germain coming to north London. Arsenal, still unbeaten this season, can take some encouragement from PSG’s miserable European record away to English sides – last season’s 4-1 defeat at Newcastle was their third-straight loss away to Premier League opposition in the Champions League.

City head to Slovenia

Manchester City will take on Champions League debutants Slovan Bratislava on a run of only one win in four games and trying to adjust to the loss of lynchpin Rodri. Pep Guardiola changed shape away to Newcastle at the weekend with Mateo Kovacic and Rico Lewis sitting in front of the defence, but they were far from their fluid best in a 1-1 draw and further refinements are clearly needed. Even so, City are clear favourites in Bratislava, where avoiding defeat will see them match Manchester United’s record of 25 games unbeaten in this competition.

Kane fit to face Villa?

Vincent Kompany will be back at an English ground on Wednesday night for the first time since leaving Burnley, but it remains to be seen if he will have Harry Kane with him for a reprise of the 1982 European Cup final. Kompany’s move to Bayern Munich following the Clarets’ relegation was one of the more surprising moves of the summer but the former Manchester City captain has enjoyed a great start to life in Germany, unbeaten in seven games and top of the Bundesliga. But Kane was forced off in Saturday’s 1-1 draw with Bayer Leverkusen and is a doubt for the trip to Villa Park as he continues to receive treatment. Villa’s return to elite European football started well with a 3-0 win away to Young Boys, but Bayern were even stronger in an emphatic 9-2 rout of Dinamo Zagreb.

Another Italian job for Liverpool

After coming from behind to beat AC Milan 3-1 in their Champions League opener, Liverpool get another look at Italian opposition on Wednesday with Bologna travelling to Anfield. Top of the Premier League and enjoying a 10-game winning streak in European group-stage matches at Anfield, Arne Slot’s side should be full of confidence and strong favourites for this one.

Celtic’s toughest test

Celtic have won every game they have played so far this season but their toughest test yet awaits in Germany on Tuesday as they take on last season’s Champions League runners-up Borussia Dortmund. The odds are stacked against Brendan Rodgers’ side. Celtic have never won a game in Germany and have won only one of their last 11 European away fixtures. Dortmund, regulars in the knock-out rounds, have been scoring for fun in recent weeks with 10 goals in their last three home games.