Lucas Leiva is Liverpool's longest-serving player, having been with the club since moving from Gremio in 2007.
The Brazilian found it tough to win over fans during the initial stages of his Anfield career but the never-say-die attitude he has displayed over the years have seen him become a firm fan favourite.
Lucas' arrival was seen as quite a coup for then-Reds boss Rafael Benitez, with a host of European clubs apparently circling.
Having broken onto the scene in October 2005, Lucas soon became the youngest player ever to win the Bola de Ouro. The honour is given to the best player in the Campeonato Brasileiro and has previously been won by Zico, Romario, Kaka and Carlos Tevez.
The youngster, nephew of former Brazilian footballer Leivinha, captained his country's U20s to the South American Youth Championship title in 2007, scoring four goals in the process.
No wonder senior coach Dunga was starting to take note. He selected the midfield battler against Al-Kuwait in October 2006, but the game was not an official FIFA tie and so did not count as his international debut. That came a month into his Liverpool career in August 2007 when he was used as a substitute in a friendly with Algeria.
Lucas, who also holds an Italian passport, made his Reds bow as a second-half sub in a Champions League qualifier against Toulouse on August 28, 2007.
The Brazilian notched up more than 30 appearances in his debut season, breaking his Anfield duck in style with a 25-yard curler in the FA Cup against Havant and Waterlooville.
Lucas was absent for the start of 2008-09 after travelling to the Olympics in Beijing, where he claimed bronze after a semi-final defeat to Argentina.
The No.21 tallied a further 39 appearances during his second season at Anfield despite stiff competition from established stars Javier Mascherano and Xabi Alonso. The highlight came when he stood in for the latter as Liverpool thrashed title rivals Manchester United 4-1 at Old Trafford in March 2009.
Alonso's departure to Real Madrid a few months later meant Lucas became an integral part of the team - and he seemed to relish his new-found responsibility. The Brazilian was voted our Young Player of the Season for 2009-10, proof of how far he'd come in the eyes of Kopites.
The following season, with Kenny Dalglish now at the helm, the likeable anchorman signed a new long-term contract before going one better than the previous year by winning the fans' Player of the Season.
In the summer of 2011, he featured in the Copa America, but the campaign ended miserably for the Liverpool man as he earned a red card during a quarter-final defeat to Paraguay.
Back in England, Lucas' performances just kept getting better in 2011-12 and he was now regarded as one of the Premier League's finest midfielders.
Unfortunately, his season cruelly ended in November when he suffered an anterior cruciate ligament injury to his knee during a League Cup victory at Stamford Bridge.
After watching from the sidelines as the Reds reached two domestic cup finals, Lucas mounted an impressive comeback and was acknowledged as an important figure by new boss Brendan Rodgers as the club departed for its summer tour in 2012.
The Brazilian began the 2012-13 campaign in Rodgers' team but suffered an unfortunate setback mere minutes into a match against Manchester City in August of that year. Three more months out of action were ordered.
To Lucas' immense credit, he achieved a return once more and, with his fitness improving with each passing week, he featured in a total of 31 matches before the season concluded.
The South American's determination and spirit was then rewarded with a new long-term contract in April 2013.
Lucas has remained a key man under Jürgen Klopp, who was keen to retain his services ahead of his first full season in charge of the club.
The manager has often made the most his No.21's versatility by deploying him at centre-half, where his ability to play out from the back has proved a real asset.