LONDON (AP) -Anyone who thought last week's loss at home to unheralded Rubin Kazan was the first crack in a crumbling Barcelona soccer team should have been at Camp Nou on Sunday.
Pep Guardiola's classy players provided the answer with a 6-1 thrashing of Real Zaragoza and could easily have scored at least three more goals. It was a strong warning to rivals in the Spanish and Champions leagues that they are not going to give up their titles easily.
If this is how Barcelona reacts to a shocking defeat, then the likes of Real Madrid, Inter Milan, Manchester United and Premier League leader Chelsea should take note.
Let's face it, all Rubin did was catch Guardiola's team on an off day.
Yet the 2-1 Champions League loss to the Russian club prompted suggestions that Barcelona was nowhere near as strong as the team that won three trophies last season when it became Spanish and European champions.
With Real Madrid bulking up its squad with such signings as Cristiano Ronaldo, Kaka, Karim Benzema and Xabi Alonso, Barcelona was under far more pressure to hold onto its Spanish league title, let alone the European crown.
Critics questioned the club for releasing free-scoring Samuel Eto'o and replacing him with the immensely talented but unpredictable Zlatan Ibrahimovic. They pointed to lapses of concentration in defense and suggested Lionel Messi's form had dropped because of Argentina's shaky form in qualifying for the World Cup.
Another loss at home would have added to those doubts. But Guardiola's team brushed Zaragoza aside and appeared unstoppable as it moved into a three-point lead at the top of the Spanish standings.
Ibrahimovic scored twice - once with a powerful free kick and the other from close range - and had another disallowed. Messi repeatedly cut through the Zaragoza defense with his dribbling, had two shots blocked by the 'keeper and finally chipped the ball over him for a goal.
Andres Iniesta and Xavi Hernandez controlled the midfield and joined the frequent spells of one-touch passing and Seydou Keita scored three goals in an overall showing that was applauded by club president Joan Laporta.
``We put in a perfect performance and we were clearly deserved winners,'' he said. ``The players were especially motivated after Tuesday's result and they showed tonight that that was just a slip-up.
``There's a long way to go in the league yet. We are playing well and with the same attitude we showed last year - humility and sacrifice. We are on the right track''.
Guardiola had special praise for Messi and Ibrahimovic, who have combined for 13 goals.
``Leo is never in doubt,'' he said. ``He's a guy who just loves playing football. It's important that we are by his side and he knows that we will always be there whatever happens.''
He said Ibrahimovic was settling into the team and becoming stronger and more dynamic.
Xavi said he was confident the team would get over the loss to Rubin.
``I already said that the game the other day was just one of those things,'' he said. ``People tend to be guided by results, but we know that if we continue playing like that (against Zaragoza) then we will almost always win. The victory helped show that we are doing things well, has helped build confidence, and has made us league leaders.''
Guardiola is likely to rest some frontline players when Barcelona begins defense of the domestic cup Wednesday against Cultura Leonesa, a third-division club that has played only one season in top-tier soccer.
Then comes a visit to mid-standings Osasuna in the league and a chance to make up for its loss to Rubin when it travels to Kazan Nov. 4.
Barcelona is in a tight Champions League group with Italian champion Inter Milan and Ukraine's Dynamo Kiev, with only one point separating first and last. It's possible that Guardiola's team needed that loss to Rubin to shrug off any hints of complacency and sharpen its act.
If that's the case and Zaragoza was the first team to feel the full force of its response, then the rest of Europe should beware.