Thomas Vermaelen is determined to prove himself at Barcelona next season after enduring a "terrible" maiden campaign at the Nou Camp.

Barca signed Vermaelen from Arsenal for £15million last summer, but the Belgian struggled to recover from a hamstring strain he suffered at the World Cup and then sustained a serious thigh injury.

Vermaelen watched on in frustration as his team-mates completed a historic treble. The 29-year-old had to wait until the final league game of the season to make his debut.

The Belgian felt uneasy about collecting winner's medals last year when he barely contributed, and regards the campaign as a low point in his career.

"I got a medal, but you don't feel like you have won the treble," said Vermaelen after playing an hour of Barcelona's 3-1 friendly defeat to Manchester United in Santa Clara on Saturday.

"I was very happy for the team, but it's not like I contributed a lot for the cups we won."

Vermaelen has come through the first two games of Barca's pre-season tour of the United States unscathed and is optimistic about maintaining his fitness in the build-up to the new campaign.

"I am very happy and very pleased to be back," the former Arsenal defender said.

"There's nothing better than to feel fit.

"Last year was terrible. It was a nasty injury, a very difficult one and I am very happy that the feeling in the legs is perfect again, like it should be.

"I feel 100 per cent now. We just started pre-season so I am adapting still but I had 60 minutes against a good opponent so I am very pleased with that."

Even if he is fully fit, Vermaelen is by no means assured of a place in Luis Enrique's starting XI, of course.

Gerard Pique, Javier Mascherano, Marc Bartra and Jeremy Mathieu are also fighting for the two centre-half places available, but Vermaelen is not fazed by the challenge that lies ahead.

He said: "In a club like this there's loads of competition so that's normal.

"We have a lot of great players. It's not easy but that's why you become a football player, to play for the best teams in the world and I am part of that."