Oriol Romeu Vidal joined from Barcelona in August 2011, signing a four-year-contract.
Primarily a deep-lying midfielder, the 6ft Catalan can also play in central defence and is renowned for his strength and his expansive passing ability.
Romeu made his debut as a late substitute in our 2-1 win at Sunderland in early September, and followed that up with 90 minutes against Fulham in the Carling Cup.
The youngster's early-season form impressed, earning him 12 consecutive appearances over the tough Christmas and New Year schedule in the heart of the Blues midfield. However, niggling injuries kept him out of action throughout much of February and March.
Romeu struggled to establish himself as a regular under the stewardship of Roberto Di Matteo, making only a handful of appearances, most of which came as a substitute.
He made his first appearance of the 2012/13 season in the Capital One Cup win over Wolverhampton Wanderers, a game which also saw him score his first goal for the club from the penalty spot.
His first league appearance of the campaign came as a second-half substitute in the 4-1 win over Norwich City when he replaced John Mikel Obi, while Di Matteo handed him a first league start in the 1-1 draw at Swansea, although he was withdrawn at the break, replaced by Ramires.
The arrival of Rafael Benitez saw Romeu begin to feature more regularly, before his progress was curtailed when he sustained a knee injury during the 3-1 win at Sunderland, subsequently ruling him out for the remainder of the season.
Romeu returned to training towards the end of the season, but the management chose not to take any unnecessary risks with his fitness.
It was announced in July 2013 that he would spend the 2013/14 season on-loan back in his homeland at Valencia.
Romeu began with Barcelona's smaller neighbours Espanyol before joining the famous Camp Nou academy in 2004, progressing through the ranks until a reserve team regular playing in Spain's second tier under former Spain international Luis Enrique.
Having overcome a knee injury during the season, he made his La Liga debut for the senior Barça side at the end of the 2010/11 campaign, coming on as a late substitute in a 0-0 draw against Deportivo La Coruna, having also appeared at the beginning of the campaign in a Spanish Supercup loss away at Sevilla.
He was a runner-up with Spain in the European Championships at Under-19 level in 2010, beaten in the final by Gael Kakuta's France.
Aged 19, he was part of the Spain squad that was competing in the Under-20 World Cup squad in Colombia at the time the move was finalised. They reached the quarter-finals before losing on penalties to eventual champions Brazil.
Oriol received an Under 21 call-up for the subsequent autumn internationals.
He was then called into the Spain squad for the London Olympics, alongside both Juan Mata and Cesar Azpilicueta, featuring in two of their three group games as they suffered a disappointing early exit.