( CNN ) -- On the day that Gareth Bale commanded headlines by joining Real Madrid in a big-money move , Lionel Messi made news by scoring a hat-trick for Barcelona in a 3-2 win against Valencia . Messi 's treble was his 23rd in the league for Barcelona and handed the away side a 3-0 advantage within 41 minutes at the Mestalla . Barcelona then had to hang on at times after Helder Postiga netted a brace just before halftime . The home side also had a pair of penalty appeals waved away by the referee . `` We could have ended with a 3-3 , 2-3 or 2-5 , '' Barcelona manager Gerardo Martino told the club website . `` Regardless of what could have happened I would leave here very pleased with how the team played . We found what we were looking for . '' Cesc Fabregas set up Messi 's first two goals after good work from holding midfielder Sergio Busquets , and summer signing Neymar linked up with the Argentine on the third . Brazilian forward Neymar and Messi started together for the first time in the league after neither found the net in the second leg of the Spanish Super Cup last week . `` There was concern about how Neymar and Messi were going to interact on the pitch after they played their first match together , '' Martino said . `` They fixed that in less than 24 hours . '' Barcelona has won all three of its league games , like arch-rival Real Madrid . Several hours before Bale 's deal was announced , Madrid defeated Athletic Bilbao 3-1 . Cristiano Ronaldo scored his first goal -- Messi has five -- with a header from Angel di Maria 's perfect cross . But it was 21-year-old Spanish international Isco and Bale 's former teammate at Tottenham , Luka Modric , who earned praise from Real Madrid boss Carlo Ancelotti . Isco , a summer arrival from Malaga , accounted for the two other goals and Modric impressed with his work rate in midfield . `` He was fantastic , '' Ancelotti told Madrid 's website , referring to Modric . Switching to Isco , Ancelotti added : `` He is playing very well and he makes it look like he 's been here for years . He has character and ability and that is very important for us . '' Dortmund on a roll . Only one team in the Bundesliga remains unbeaten through four games -- and it 's Borussia Dortmund . Dortmund beat Eintracht Frankfurt 2-1 thanks to a double from midfielder Henrikh Mkhitaryan . Mkhitaryan scored his first two goals for Dortmund after his $ 35 million transfer from Shakhtar Donetsk . It was n't a vintage display by the Champions League runner-up but manager Jurgen Klopp was n't arguing with the result . `` We have to play better football , there 's no question , '' Klopp was quoted as saying by AP . `` I 've seen a few weaknesses in our build-up play and ideally we need to defend better . Still , with 12 points after four games , this is complaining at a high level . '' Defending champion Bayern Munich trails Dortmund by two points . In Ligue 1 , Monaco moved atop the table with a 2-1 win over previously unbeaten Marseille . Marseille led 1-0 at home before Radamel Falcao and Emmanuel Riviere scored in the second half . Falcao and Riviere have already combined for eight goals this term .
Lionel Messi scores three first-half goals for Barcelona on the road against Valencia . Valencia rallied to make the game close thanks to two goals from Helder Postiga . Valencia and Isco starred for Lionel Messi in a two -1 win over Helder Postiga . In Germany , Real Madrid runner-up Borussia Dortmund also stayed perfect .