5 talking points ahead of the Champions League quarter-final first legs

The first legs of the Champions League quarter-finals take place this week. Here, Press Association Sport looks at some talking points ahead of the games.Uniteds Barca challengeManchester United come up against Lionel Messi (Nick Potts/PA)Ole Gunnar Solskjaers Manchester United pulled off a shock to beat Paris St Germain in the last round and it was probably that result that clinched the managers job full time for the Norwegian. Performances since have tailed off slightly and the challenge ahead of them as they face Barcelona and, of course, Lionel Messi, is huge. Barca are closing in on an eighth LaLiga title in 11 years and will be keen to make the most of Real Madrids elimination from the Champions League.Citys quadruple pushManchester City boss Guardiola has played down quadruple talk (John Walton/PA)Manchester City are the favourites for the Champions League and with good reason given their sustained excellence in four competitions this season. Manager Pep Guardiola described the quadruple as almost impossible at the weekend but it is actually far from inconceivable. The Champions League has been the one hurdle they have consistently failed to clear, however. Guardiola has often referred to a lack of experience on the European stage for that, although that may not be relevant in this round as they face a Premier League rival in Tottenham.All-English clashManchester City will be the second visitors to Tottenhams new stadium (Nick Potts/PA)Citys tie with Spurs is an enticing one, starting with the first leg at the London clubs new stadium on Tuesday. Citys superiority is evident in the 16-point gap between the two sides from second to third in the Premier League but a big domestic advantage counted for nothing when they faced Liverpool at the same stage last year. Then City lost 3-0 in the first leg at a fevered Anfield. Spurs will hope the atmosphere at their new stadium will work in their favour, although Kevin De Bruyne has dismissed it. I dont care about the stadium, he said.Liverpool eyeing last four againLiverpool go into their clash with Porto in good form (Martin Rickett/PA)Last years beaten finalists Liverpool may fancy their chances of reaching the last four again after being drawn against Porto, a side they beat 5-0 in the first leg of their last-16 tie last season. The Reds priority may be the Premier League but defeat here would represent a big missed opportunity. Porto are also without veteran defender Pepe for Tuesdays first leg at Anfield through suspension.Ronaldo fitnessCristiano Ronaldo has had a fitness scare in recent weeks (Martin Rickett/PA)Five-time world player of the year Cristiano Ronaldo has been out for the past two weeks with a thigh injury but is expected to return for Juventus clash with Ajax. Manager Massimiliano Allegri took no risks against AC Milan at the weekend, holding the Portuguese back in a bid to ensure his fitness for Wednesday in Amsterdam. Ronaldo, who has won this competition five times, relishes such occasions.(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
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