The 31-year-old Brazilian goalkeeper became a Liverpool player on 15 July 2011 after signing from AS Roma. Doni or to give him his full name Doniéber Alexander Marangon had been on the books of five different clubs in his homeland before moving to Europe in 2005. He had, however, only played competitive matches for three of those clubs so was relatively inexperienced when he joined Roma at the age of twenty-five. In the 2005/06 season Doni played in 28 of Roma’s 38 Serie A matches as the club from the capital finished runners-up to Internazionale. He missed only seven league matches over the next two seasons as he established himself firmly as the club’s first-choice goalkeeper. Although Roma could not break Inter’s stranglehold on the Italian championship, they did win the Coppa Italia in both 2007 and 2008. Internationally, Doni was first capped in 2007 and later in the same year won the Copa America with Brazil where he played a big part in the semi-finals saving two penalties in the penalty shoot-out against Uruguay.
Reds' director of football Damien Comolli said of Doni's capture: "I spoke to Lucas about Doni and he was very complimentary about him as a person and as a goalkeeper, so I think it's a great deal for us. He is suited to English football. He is big and good in the air and his distribution is quick as well. When you play for Roma for years and years, the pressure at that club in that city is tremendous, so the fact he can handle that shows he can take anything." Although Doni was on the substitute's bench when Pepe Reina was sent off at Newcastle early in April 2012, Dalglish had already made his three changes at the time of the dismissal. With Reina's suspension being for three matches, the Brazilian was expected to play in League matches against Aston Villa and Blackburn Rovers as well as the Wembley FA Cup semi-final against Everton. However, he was himself dismissed at Blackburn and that ruled him out of the important cup-tie the following weekend. Doni had not been part of Liverpool’s plans in 2012/13 due to “personal issues”, which he finally shed some light on in January 2013 when he had moved back to his first club, Botafogo de Ribeirão Preto. “I almost ended up on the other side. I had a heart attack for about 25 seconds,” Doni revealed. “I always had an arrhythmia and during some tests in Liverpool suffered a cardiac arrest. I’ve been to one of the best doctors in Europe who looked at me carefully. He’s asked me to stop for a few months. Now I have to stay put until April, then I can return to the field. I want to play in the fourth division of the 2014 Paulista championship.” Unfortunately, Doni had to retire from the game in August 2013 due to cardiovascular disease. "God doesn’t want me to play football anymore,” he told Estadio. “It’s sad that I have to quit, especially because my son wanted to see me play again.I would have liked to continue for him, but I can’t do anything about it. I’ve already died once.”
In 2018 it was reported that Doni had a hand in the arrival of Allison Becker at Anfield, having advised goalkeeper coach John Achterberg to keep an eye on him whilst he as at Internacional.