I won the Champions League with Liverpool, but my career was cut short due to a persistent knee injury. I was known for my strong tackling and work rate in midfield. Despite being a crucial player, my time at Anfield was brief. Who am I?

1. I joined Liverpool from a Portuguese club.
2. I was part of the squad that won the 2005 Champions League final.
3. I was a very combative midfielder.
4. My career was plagued by injuries, forcing me into early retirement.