Xabi Alonso has told German football magazine kicker that not winning the Premier League with Liverpool remains one of the biggest regrets of his career.
Alonso, who retired from football at the end of the season after a final spell at Bayern Munich, won the Champions League and the FA Cup during his five seasons at Anfield.
He came close to winning the Premier League in 2008-09, when Liverpool finished as runners-up to Manchester United.
"I would include not winning the Champions League with Bayern and the Premier League with Liverpool," Alonso said when asked about his regrets.
"We won practically everything -- the Champions League, FA Cup but not the Premier League."
He said he also regretted missing out on the title with Real Sociedad in 2003, when Real Madrid snatched the crown, but added: "If I had won all of them, my trophy collection would have simply been too complete."
On his time at Liverpool, Alonso added: "Liverpool has its own legend and history that appeals to everyone who loves football. It gripped me too. Anfield gripped me, of course the Premier League too because we were doing well.
"In 2005, we won the Champions League in my first season, and it went 'click.' And when Liverpool grips you, it grips you for life."
The 35-year-old, who won the Bundesliga title in his final season, said he was looking forward to his retirement.
"I'm definitely going to buy a motorbike and go on a trip this summer," he added. "It will be a racing bike, not the biggest but not the smallest neither.
"I've always liked motorbikes, I like the freedom that you get on a motorbike and I couldn't enjoy before.
"Generally though I'm looking forward to more free time, free weekends, as a new stage of my life begins."
ESPN FC's Bayern Munich correspondent, Mark Lovell, contributed to this report.