It was a sombre mood at the Camp Nou as Barcelona took on Real Betis in their first La Liga game of the season following the terrorist attacks in the city earlier this week. But Barcelona fans went home happy after their side claimed all three points in a 2-0 win even though they didn't turn up in numbers (less than 57,000 fans were at the stadium as many stayed away).An own goal from Alin Tosca and a Sergi Roberto goal within three minutes of each other in the first half were enough to give Ernseto Valverde three points on his league debut as manager.Without Luis Suarez, Lionel Messi led the line (sometimes dropping deep as a false nine) but try as he might, he only hit the post three times apart from narrowly missing the target on a few other occasions.Here's how Twitter reacted to the game.#TotsSomBarcelona pic.twitter.com/XndUMBLi2H— FIFA.com (@FIFAcom) August 20, 2017?? Today's crowd at Camp Nou, 56,480 #BarçaBetis #ForçaBarça pic.twitter.com/ORwCTkoMes— FC Barcelona (@FCBarcelona) August 20, 2017Lionel Messi fails to score at home in @LaLigaEN for the first time in 2017 #Messi pic.twitter.com/xgdjQhqoHZ— Sky Sports Statto (@SkySportsStatto) August 20, 2017Keep saying on commentary that Messi looks unhappy. It's a few days after the attack on Barcelona. He's clearly being respectful.— Gary Lineker (@GaryLineker) August 20, 2017Even when Messi misses it looks good. 10 shots on goal with a hat-trick for hitting the woodwork. 3 shots that narrowly missed the target.— Rohith Nair (@RohithNair) August 20, 2017#Messi still not at #LaLiga goal number 350 just yet.— Jason Pettigrove (@jasonpettigrove) August 20, 2017Most La Liga matches needed to score 1st goal for FC Barcelona this century: 194 Mascherano, 96 SERGI ROBERTO, 52 Oleguer, Puyol #FCBLive— Gracenote Live (@GracenoteLive) August 20, 2017Nélson Semedo's LaLiga debut by numbers:100% take-ons completed100% tackles won93% pass accuracy2 clearances1 chance created? pic.twitter.com/c7UnbMW5Xp— Squawka Football (@Squawka) August 20, 2017Intelligent half from S. Roberto. Runs from midfield, positional adjustment to accommodate "winger" Álcacer. Doesn't matter where, fits.— Aldo Sainati (@aldosainati) August 20, 2017I want a girl who can read my mind like Busquets reads a game. #FCB— Amit Mishra (@Leamitmishra) August 20, 2017Camp Nou chanting "Bartomeu dimissio, Bartomeu dimissio (Bartomeu resign, Bartomeu resign)."— Leo Messi (@messi10stats) August 20, 2017The challenge from @Mascherano is timed perfectly! #LaLiga #FCBBetis pic.twitter.com/6DQGmxtUsB— beIN SPORTS (@beINSPORTS) August 20, 2017Keep talking crap about Mascherano. Dude risks his anus match in and match out for club and country.— Roy Nemer (@RoyNemer) August 20, 2017The last time Sergi Roberto scored for Barcelona was on March 8th against PSG at the Camp Nou in the CL (6-1) #fcblive [md]— FC Barcelona Fl (@FCBarcelonaFl) August 20, 2017One thing we learned about Barca vs Betis game is Ronaldo could never pull a 10/10 performance without a goal & assist, Messi as usual did ? pic.twitter.com/HN5ILjzaRl— BreatheGreatness (@BreathingMessi) August 20, 2017Lets remember how we lost La Liga last season before underestimating wins against the likes of Betis. We hadn't play this well for long.— Ramzi ?? (@footballmood) August 20, 2017Ter Stegen pic.twitter.com/V6U8RBsbl3— Todo_Betis (@RBB_betis_1907) August 20, 2017Messi hits the post thrice today ? pic.twitter.com/fh8EZQL9YU— Football Obsession (@Footy_Obsession) August 20, 2017