Manchester United begin their Europa League campaign this week but manager Sir Alex Ferguson still insists his team are "not far away" from the quality of Real Madrid and Barcelona.
United have reached the final of Europe's flagship competition three times in the past four seasons but surprisingly went out at the group stage this term after two damaging results - a draw and a defeat - against Swiss side Basel.
However, Ferguson is convinced that was merely a blip and his side can soon get back to the level of the top European sides.
"I feel we had the ability to go all the way to the final," Ferguson told FIFA.com. "Luck wasn't on our side, but I think we've got the ambition to compete with Barcelona and Real Madrid, and I don't feel we're that far away from them. I'm sure we'll show that soon.''
Although United have suffered in Europe this season, the Premier League champions are just two points behind leaders Manchester City domestically and temporarily topped the table after beating Liverpool on Saturday.
Ferguson is determined to push neighbours City all the way to the title this season to help compensate for being dumped out of the Champions League, despite having to do so without key members of his squad.
"We've had our ups and downs and we've been unlucky with injuries. We've had a lot of them, which you don't expect, and we've got people like Nemanja Vidic and Darren Fletcher out for the whole season," Ferguson said.
"You can replace your best players for a game or two, but you really notice the difference over a longer period, and that's what's happened to us.
"Even so, we're fighting hard to win the Premiership again and there's a lot of merit in that. Obviously I'm optimistic about our chances.''
United have a high-profile fixture against Ajax at the Amsterdam ArenA on Thursday to kick-off their Europa League campaign and Ferguson has said he will play his strongest team.