Brentford defender Harlee Dean has completed his move to Birmingham City, with the Bees receiving a fee believed to be in the region of £2million.
The 26-year-old first moved to Griffin Park on loan from Southampton in November 2011 and it was made permanent the following summer.
His first full season at Griffin Park culminated in play-off heartache against Yeovil, although the defender did manage to get his name on the scoresheet.
The second season saw the Bees end their exile from the top two divisions with Dean playing a major role, despite injury, in a 1-0 win at Leyton Orient which saw the west Londoners down to 10 men, after James Tarkowski's red card, survive wave after wave of attacks to turn the tide of the promotion race.
The first season in the Championship saw him in and out of the side at the start of the season and he went from villian to hero against Fulham, making a mistake for the Whites' opener but redeeming himself by scoring the equaliser.
Dean appeared set to depart at the end of the 2015/16 season with his contract running down but, after Tarkowski forced through a move to Burnley, a new deal was accepted and the defender became captain last term.
The leadership role led to an increased level of performance and the 26-year-old was named player of the season but with the Bees unable to agree a new contract, the club looked to cash in.
Brentford head coach Dean Smith told the club's official website: “I would like to thank Harlee for his commitment to Brentford over the last six years.
"He was our captain last year and played to a level which earnt him recognition from supporters and peers, culminating in being awarded the Player of the Year award.
"He has been a major player for the club over a successful period and a player I have thoroughly enjoyed working with.
"Unfortunately, we could not come to an agreement for a new contract and he has chosen to move on, we all wish him well for his future career.
Dean's departure leaves a void in the Brentford defence, that is expected to be filled by John Egan, while Chris Mepham is expected to be promoted to the first team.
Co-Director of Football Phil Giles added: "Harlee has been an integral part of what this Club has achieved over the last few years.
"Not only is he a good player, he was someone who I found to be engaging company and who always had time for others, particularly with young fans at our open days.
"A great example of that was when he assisted at a road traffic accident outside Griffin Park after a game against Nottingham Forest in November 2015.
"On behalf of everyone at Brentford I'd like to thank him for everything he has done for the club."