Marko Marin's transfer from Werder Bremen was agreed in April 2012, with the Serbian-born German linking up with his new team-mates at the beginning of pre-season for the 2012/13 campaign.
Marko even turned up early to work on his fitness during the summer, and it looked to have paid dividends after some impressive displays on tour in America, and he grabbed his first Chelsea goal on his debut against Seattle Sounders.
Able to play as a winger as well as a central player, Marin is 5ft 7in (170cm) tall. His progress stalled slightly towards the end of pre-season with a hamstring injury, meaning a wait for a competitive bow.
After missing the start of the season through injury, Marin made his Chelsea debut during the 6-0 win over Wolverhampton Wanderers in the Capital One Cup, replacing Juan Mata midway through the second half.
His first league start came in the 1-0 home defeat to Queens Park Rangers, although he was replaced by Eden Hazard midway through the second half.
Marin scored his first goal for the club after coming on as a substitute in the 4-1 win against Wigan Athletic.
Born in Bosnia and Herzegovina, Marko moved to Germany with his family at an early age and became a professional player at Borussia Monchengladbach before moving north to Bremen in the summer of 2009.
He made 87 Bundesliga appearances for the club prior to agreeing to sign for Chelsea, scoring 12 goals. He also played in the 2010 German Cup Final when his side lost to Bayern Munich.
Marko played for Germany Under-21s, making his debut for the senior Germany side in May 2008 prior to being part of the squad that won the European Under-21 championships in 2009.
For the senior team, he made two substitute appearances during the 2010 World Cup in South Africa and had 16 caps and one goal to his name at the end of the 2011/12 season.