PARIS: Arsenal beat Paris Saint-Germain 2-0 in their heavyweight Champions League clash on Tuesday, while last season’s beaten finalists Borussia Dortmund gave Celtic a harsh reality with an emphatic 7-1 win in Germany. Dortmund were the biggest winners on a night that also saw Barcelona, Manchester City and Inter Milan claim one-sided victories and Champions League debutants Brest won 4-0 at Red Bull Salzburg. Arsenal’s clash with French champions PSG in London was the big game of the day as the second round of matches got underway in the new format of Europe’s elite club football competition. The Gunners were worthy winners as Kai Havertz headed home Leandro Trossard’s cross to open the scoring in the 20th minute and Bukayo Saka doubled their lead before half-time when his free-kick from the right evaded all who got inside. PSG saw Nuno Mendes hit the outside post in the first half, while Joao Neves hit the woodwork after the break, but the visitors could not get back into the game. It is the first Champions League win of the season for Mikel Arteta’s Arsenal, who drew 0-0 with Atalanta in the first leg two weeks ago. “Really, really happy with the performance,” Arteta told Amazon Prime TV. “The Champions League brings different demands, but I think we handled it really well.” Dortmund are currently top of the 36-team league after beating Scottish champions Celtic in their first game in Germany following a 3-0 win at Club Brugge. Karim Adeyemi scored a first-half hat-trick for Dortmund, who led 5-1 at half-time. Emre Can opened the scoring from the penalty spot before Daizen Maeda equalised, but it was Adeyemi who got to the heart of the action. Serhou Guirassy netted a penalty before the break to make it 6-1 midway through the second half, with substitute Felix Nmecha later wrapping up the win. It is Dortmund’s biggest win in the Champions League, along with a 6-0 win away to Legia Warsaw in 2016. “There’s no such thing as a perfect game, but it was very, very good,” Can said. “This has to be the standard we want to set.” Barcelona thrashed Swiss champions Young Boys 5-0 to bounce back from a 2-1 defeat in Monaco a fortnight ago and their first La Liga defeat of the season at Osasuna last weekend. Robert Lewandowski scored twice either side of goals from Raphinha and Inigo Martinez before a late own goal from Mohamed Ali Camara wrapped up victory. “After the game against Monaco in the Champions League, we knew we had to give a quick answer in the next game, which was this one, and we did that well,” Raphinha told TV station Movistar. 2023 Champions League winners Pep Guardiola’s City comfortably won 4-0 at Slovan Bratislava in Slovakia with goals from Ilkay Gundogan, Phil Foden, Erling Haaland and James McAtee. Inter, who lost to City in the final in Istanbul two seasons ago, won by the same scoreline at home to Crvena Zvezda Belgrade. Hakan Calhanoglu got Inter going with a stunning early free-kick before Marko Arnautovic, Lautaro Martinez and Mehdi Taremi netted in the second half, the second from the penalty spot. German champions Bayer Leverkusen claimed their second successive win of the season as Victor Boniface’s second-half goal saw them beat AC Milan 1-0. Meanwhile, French Champions League newcomers Brest also made it two wins from two with a remarkable 4-0 away win at Salzburg in Austria. Senegalese striker Abdallah Sima, a striker on loan from Brighton who scored twice in the match-winner against Sturm Graz two weeks ago. Mahdi Camara and Mathias Pereira Lage also found the target as Brest scored three of their goals in the space of 10 minutes in the second half. Salzburg, Slovan Bratislava and Young Boys are the last three in the starting order. VfB Stuttgart and Sparta Prague drew 1-1 as Enzo Millot put the Germans ahead and Finland international Kaan Kairinen equalized before the break. PSV Eindhoven and Sporting Lisbon also drew 1-1. Jerdy Schouten’s opener for the Dutch champions was canceled out by Daniel Bragancy’s late equaliser.