Xavi has admitted that he is "angry" after Barcelona crashed out of the Champions League.
Defeat to Bayern Munich confirmed that the Catalan club will drop into the Europa League, with Benfica joining the German side in the knockout stages of the top-tier competition after victory over Dynamo Kyiv.
It is the first time since the 2003-04 season, when Barcelona only qualified for the UEFA Cup, that the club will not compete in the knockout rounds of the Champions League.
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Xavi replaced Ronald Koeman in November but has thus far struggled to arrest Barcelona's struggles, and the former midfielder conceded that he will have to "change a lot" after a "hammer blow" of a defeat.
"Bayern dominated us," Xavi said. "We always want to dominate but it was the opposite here. We must demand more. We're Barca. This must be a point of inflection to change the dynamic and many more things.
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"This is the Champions League, but this is also our reality. It's the situation we're in.
"I'm angry. This is the reality and it p***** me off. We have to tackle it face on. There's nothing else for it."
Bayern Munich have now beaten Barcelona thrice in 16 months, with an aggregate scoreline of 14-2 across those three meetings.
Xavi's side sit seventh in La Liga after defeat to Real Betis at Camp Nou last weekend.
The Spaniard, who made 767 appearances for the club as a player, confirmed that Barcelona will now try and win the Europa League, but made clear that the club do not "belong" in the competition.
"A new era starts today," he said. "We start from zero. Our objective is the Champions League, not the Europa League but that is our reality now and we have to try and win it.
"I've seen how tough the reality is. I hoped we would compete better. Bayern are better. That's the reality. But we're going to work hard and give our all so that this doesn't happen again. It's a feeling of helplessness.
"We have to start to get Barca back where they belong, which is not in the Europa League. This is also a hammer blow for me as a coach. We will work hard to bring Barca back, but we have to change a lot, of course."
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FC Bayern Munich