Former Arsenal captain Cesc Fabregas accepts he faces a battle to find a place in Barcelona's midfield.
Fabregas, 24, joins a Barca side widely regarded as one of the best in history and one that has picked up 10 pieces of silverware in just three years under Pep Guardiola.
The former Arsenal captain admits it is a huge test for him, but one he is not afraid of.
"It's the biggest challenge of my life," he said.
"I've chosen the most difficult path. It's a difficult challenge but I'm not afraid, just the reverse. I will fight until the last drop of sweat."
Barcelona are next in action on Wednesday night when they host arch rivals Real Madrid in the second leg of the Spanish Supercup, having drawn Sunday night's first leg 2-2 at the Bernabeu.
"I didn't see the first leg last night as I was flying over," he said on Monday. "But physically I'm fine and ready for everything. It's up to the coach if I to play or not. I'm going to work very hard as always and enjoy it."
