BARCELONA, Spain (AP) ― Carles Puyol reluctantly quit football on Thursday, his knees no longer able to endure the demands of the Barcelona defense after 15 years, the most successful period in the club’s history.

At an organized send-off at the Camp Nou, Puyol said his goodbyes having won 21 trophies since his debut during the 1998-99 season, with nagging knee injuries having forced him out.

“I gave everything. (But) we couldn’t find a solution (to the injury) though we never stopped trying,” said Puyol, who ruled out playing for any other club due to his knee injury. “I’ll keep trying (to get better) but, now, without the pressure of playing.”

Puyol made just under 600 appearances for the club, and as the captain he led the Catalan club to three Champions League titles and six Spanish league trophies.

“For me this is the end of an era. A new one begins and I wish I will enjoy it as much as I’ve enjoyed this one,” Puyol said. “I can’t believe the career I’ve had. I‘ve lived the dream of millions of children.”

Puyol made 100 appearances for Spain, winning the 2010 World Cup following the European Championship in 2008.

Puyol said his best memory was after beating Manchester United in the 2011 Champions League final, when he handed the captain’s armband to teammate Eric Abidal so he could lift the European Cup first. Abidal had been battling liver cancer.

“You have always looked after your teammates. Those who needed you, those newly arrived, those injured, or those who wouldn’t play very often,” club and Spain teammate Xavi Hernandez said. “Fifteen years in the first team means a lot.”

With goalkeeper Victor Valdes set to exit this summer, Puyol did not see their departures as the end of the current cycle.

“It’s not the end of a Barca cycle. One stage has come to an end but this team is strong and young,” said Puyol, who would like to continue working at the club.

“In the next few weeks I have a lot of things to think about. One thing that I’m motivated about is to be involved with the club. Working with the youth program is something I’d enjoy more than being a coach.”

Barcelona faces Spanish leader Atletico Madrid in a winner-takes-all league finale on Saturday, when the defending champion could yet lift its fifth title in six seasons.

“It’s been a very difficult season, mostly due to the off-field problems than on-field, but I’m confident it will end well and we‘ll win the league,” said Puyol, who also lent support to embattled coach Gerardo Martino as the Argentine faces reports he will be fired regardless of the result on Saturday.

“It pains me that I couldn’t have played the minutes I would have liked. I tried. He maintained his confidence with me since the start of the season. He always tried to motivate me.”